SECM/13/01 COMMON FACTORS INFLUENCING THE … - ICSECM 2013.pdf · construction works of those...

1

SECM/13/01

COMMON FACTORS INFLUENCING THE PERFORMANCE OF ROAD CONSTRUCTION

PROJECTS IN SRI LANKA- THROUGH EMPLOYERS’, ENGINEERS’ AND

CONTRACTORS’ PERSPECTIVE

Sirimevan Wijekoon

Faculty of Engineering, University of Peradeniya

Email: [email protected]

Abstract

Road development is an important component of the economic improvement in Sri Lanka, and

accordingly, large number of road network improvement projects has been planned and the

construction works of those projects are in progress. However, it is learned that the majority of these

projects has not performed to the expectations, especially within time, cost, and quality standards, due

to various factors. Accordingly, a study to identify the common factors influencing the performance

of the road construction projects has been undertaken. A list of factors identified during the previous

study has been selected for a response survey among the Employer‟s Representatives to find out the

extremely significant factors influencing the performance of the road projects according to their

perspective. A sample comprising thirty engineers, representing national and provincial road

authorities has been selected for the response survey in which twenty two of them have responded.

Each responded was requested to provide their agreement or disagreement by indicating “Yes” or

“No” to each factor in the list.

Data analysis was carried out by allocating 1 and 0 for the “Yes” and “No” responses, respectively.

Factors obtained highest marks have been selected as the significant factors influencing the

performance of the road construction projects according to the Employer‟s Representatives. Those

factors are ranked according to their marks, and compared with the factors identified from the

previous study conducted among the Engineer‟s and the Contractor‟s Representatives.

Eighteen common factors significantly influence the performance of the road construction projects

identified from both studies, and are: timely issue of instructions by the Engineer; good working

relationship with the Employer, Engineer & the Contractor; construction manager‟s ability to manage

people at work; technical ability & construction knowledge of contractor‟s staff; discussion with the

Employer, the Engineer & the Contractor on construction issues and constraints at a regular intervals;

condition/reliability of the construction plant & equipment; leadership qualities of the Engineer;

authority to take day-to-day decisions by the Engineer or his assistants; previous experience of the

construction team working on similar projects.

Engineer‟s technical ability; selection of a construction manager with proven track record at the start

of the construction work; conducting progress review meetings and site inspections at appropriate

intervals; Engineer‟s qualifications and experience; providing effective assistance to the construction

team to take decisions as required on time; allowing the Engineer to take decisions and supporting

such decisions by the Employer; understanding of the responsibilities by various members of the

construction team; academic and professional qualifications of the Engineer; Contractor‟s knowledge

on construction methods

Keywords: Road Construction, Common Factors, Performance, Sri Lanka

mailto:[email protected]

2

SECM/13/02

RESOURCE CONFLICT RESOLUTION AND COORDINATION AT CONSTRUCTIN SITE

Irfan Anjum Manarvi1, Raja Ibadat Sajjad

2

1PSDM, EM Department, Center for Advanced Studies in Engineering, Islamabad, Pakistan.

Telephone: Pak: 0092 3465173113, UK: 0044 7448502395


2EM Department, Center for Advanced Studies in Engineering, Islamabad, Pakistan.

Telephone: 0092 3245477040


Abstract

Construction management deals with successful completion of a construction project in the scheduled time

and allocated budget while keeping quality and safety implementation in parallel. Construction sites are

always under stress due to scarce resources which usually be the cause of poor quality of coordination and

eventually becomes conflicts between the team members of a construction site. The goal of this paper is to

amend the traditional organizational chart of a construction site in developing countries like Pakistan; and to

monitor the progress; and to resolve the conflicts between team members due to resource deficiencies on a

construction site with the help of wireless network and direct the resources where the need is more effective

considering the critical path. The resources discussed in this paper are machinery and material required for

the execution of the project. This amendment will not only contribute to conflict resolution but also increase

the coordination between team members to minimize the waste of motion which will contribute to the

timely completion of project within the specified budget.

Keywords: Construction management, construction site, conflict, coordination, wireless network.



3

SECM/13/03

THE EFFECT OF EASY GOING STEEL ON KBF'S RESPONSE MODIFICATION FACTOR

Mahmoudi, M. 1, Vatani Oskouie, A.

2, Havaran, A.

3

1Faculty of Civil Engineering, Shahid Rajaee Teacher Training University, Iran

Telephone: +982122970021; Fax: +982122970021

E-mail: [email protected]


Telephone: +982122970021; Fax: +982122970021



Telephone: +982122970021; Fax: +982122970021


Abstract

The knee bracing steel frame (KBF) is a new kind of energy dissipating frame, which combines

excellent ductility and lateral stiffness. In Knee-Braced Frames, KBF, one end of diagonal brace is

connected to knee element rather than the beamcolumn joint. In fact, knee element as a hysteretic

damper is designed and detailed to behave like a structural fuse such that by sustaining controlled

inelastic deformations and dissipating seismic energy.Lower strength steel is used for the knee

element according to the general concept of easy-going steel (EGS).The knee element made of and

easy-going steel yields in less displacement and so the energy dissipation capacity is significantly

improved. In this articlethe effect of easy going steel on KBF's Response modification factor will be

considered. For this reason several frames with similar dimensions but various heights are designed

according to Iranian code of practice for seismic resistant design of building, knee elements replaced

with knee elements made of EGS. And then based on non-linear Incremental Dynamic Analysis

(IDA); the seismic parameters such as behavior factor and performance levels are compared, It was

observed that the knee element made of easy-going steel had significantly better behavior.

Keywords: Knee bracing steel frame, Easy-going steel (EGS), Increment Dynamic Analysis (IDA),

Response modification factor (R).




4

SECM/13/04

INCORPORATING FRACTURE MECHANISM IN THE DESIGN OF REINFORCED

CONCRETE STRUCTURES

Saad Ullah1, Musaad Zaheer

2, Waseem Khaliq

3

1School of Civil & Environmental Engineering, Undergraduate Student,NUST, Pakistan

Telephone:00923335190440,


2School of Civil & Environmental Engineering, MSc Structures (Cardiff UK), NUST, Pakistan

Telephone: 003215291990,


3School of Civil & Environmental Engineering, PhD Structural Engg(MSU, USA), NUST, Pakistan

Telephone:003074908019,


Abstract

Fracture Mechanics is all about deciphering how cracks propagate, where are they going to burst up

next, are they going to propagate or just stop where they are? There has to be some type of force or

forces acting on elements which tend to fail it in fracture. To answer all these questions, we define

Facture Mechanics as a thorough study of facture and the behaviorof crack. Fracture Mechanism can

be utilized to provide all such types of basic questions which arise during the design and analysis of

structural elements. The three major fracture propagation modes are required to be considered when

designing using the approach of Fracture Mechanics.

The observation made from the test results said cracks are not continuous rather they tend to overlap

and branches exist. We visualized cracks in terms of fracture energy, which is the minimum amount

of energy required to propagate a crack in a structural element. The said fracture energy is provided

by external loadings which tend to open up the pre-existing microcrackswhich tend to overlap and

grow in size. The fracture energy, stress intensity factor, fracture toughness and failure modes are the

main parameters around which the fracture mechanics revolves. The end product of the study is to

utilize the fracture mechanism in design and analysis of Reinforced Concrete Structures. Research

focuses and utilizes the analytical concepts for calculating Crack Mouth Opening Displacements and

Crack Propagation. These results will be utilized to determine possible ways for design improvements

in RC structures.

Keyword: Structural Design, Fracture Mechanics, Analysis Using Fracture Mechanics Approach

5

SECM/13/05

COMPARATIVE STUDY AND ANALYSIS OF MULTI-STORIED BASE ISOLATED

BUILDING

Shakir Gani1, Anand M.Gharad

2

1Department of Civil Engineering

Shri Ramdeobaba College of Engineering and Management, Nagpur, India.

Telephone: 09860659464;


2Structural Engineering, Department of Civil Engineering

Shri Ramdeobaba College of Engineering and Management, Nagpur, India.

Telephone: 7385060708;


Abstract

Base isolation technique is one of the most widely implemented seismic protection systems in

earthquake prone areas. The term „base‟ refers to the foundation of a structure and „isolation‟ refers to

reduced interaction between the ground and the structure resting over it. Base isolation is a very

effective way to counteract the damaging component of seismic forces and is one of the most widely

implemented and accepted seismic protection systems. The mechanism of the base isolator increases

the natural period of the overall structure, and decreases its acceleration response to earthquake /

seismic motion.

A multi-storied R.C.C building with lead rubber bearing is introduced throughout this study.

Validation of SAP2000 for base isolation technique using a mathematical model is carried out.

Comparison between base shear values considering fixed base for the static and dynamic analysis is

shown. Also the comparison between the base shear values of fixed and isolated base considering

dynamic analysis (response spectrum and linear time history) is explored. For response spectrum

analysis, the reduction in base shear value for base isolated building is upto 62% whereas for the

same base isolated building and for linear time history analysis, this reduction is upto 85% - 90%.

Keywords: Base-Isolation, Earthquake, Lead Rubber Bearing, Base Shear, Static Analysis, Response

Spectrum Analysis, Time History Analysis.

6

SECM/13/07

IMPORTANCE OF BUILDING FLUSHOUT BEFORE OCCUPANCY

Kelum Hemaka Siriwardhena1, Subhashi Kumari Ranathunga

2

1MERCURY International LLC, UAE.

Telephone Number - 00971561527094; Fax Number - 0097144215943


2Hunter Douglas Middle East FZE, UAE.

Telephone Number - 00971554796401; Fax Number - 0097148863301


Abstract

Building Flush-out is mandatory requirement in LEED (Leadership in Energy and Environmental

Design) certified projects. The purpose of the flush-out is to achieve the LEED credit EQ-3.2;

Construction Indoor Air Quality (IAQ) Management Plan before Occupancy. The intent of this credit

is to prevent indoor air quality problems resulting from construction/renovation process, in order help

sustain the comfort and well-being of construction workers and building occupants.

This paper investigates the following two flush-out options and sets out the recommendations for the

development and implementation of an IAQ Management Plan for the pre and post occupancy phases.

Option 1 – After construction ends, prior to occupancy and with all interior finishes installed perform

a building flush-out by supplying a total air volume of 14,000 cubic feet of fresh air per square feet of

floor area while maintaining an internal temperature of at least 15.5ºC.

Option 2 – If the occupancy is desired prior to completion of the flush-out, the space may be occupied

following delivery of a minimum of 3,500 cubic feet of outdoor air per square feet of floor area to the

space. Once a space is occupied, it shall be ventilated at a minimum rate of 0.30 cfm/sq.ft. of outside

air. During each day of the flush-out period, ventilation shall begin a minimum of three hours prior to

occupancy and continue during occupancy. These conditions shall be maintained until a total of

14,000 cu.ft/sq.ft of fresh air has been delivered to the space.

The project team will need to include the flush-out period as part of the overall construction schedule

and determine what limited commissioning or set-up activities can occur in the building during the

flush period. The USGBC (United States Green Building Council) has ruled that absorbent

furnishings cannot be moved into a building until the flush-out has been completed. Similarly,

painting touch-ups and other punch-list items that involves VOC (Volatile Organic Compound)-

emitting materials cannot be performed during the flush out period.

Keywords: Flush-out, Indoor Air Quality, USGBC, Volatile Organic Compound, LEED




7

SECM/13/08

LOCAL SEISMICITY AND POSSIBLE GROUND MOTION PARAMETERS FOR SRI

LANKA

W.G.J. Prasanna1, S. Venkatesan

2, P.B.R. Dissanayake

3

1School of Engineering and Science, Victoria University, Australia.

Telephone: +61 3 9919 4732


2School of Engineering and Science, Victoria University, Australia.

Telephone: +61 3 9919 5235; Fax: +61 3 9919 4139


3Department of Civil Engineering, University of Peradeniya, Srilanka.

Telephone: +94 777 809895; Fax: +94 81-4476797


Abstract

A generic study has been undertaken in identifying possible seismic sources located within Sri Lanka,

considering the country in the local context. Seismic activities reported within the country indicate a

close correlation with the local geotectonic setup which comprises of certain active features such as

lineaments and faults, thrust/shear zones and tectonic movements of individual mini-plates.Two

probable seismic zones were identified; 1) Area around capital city-Colombo 2) Mahawelli shear

zone. A comparison of ground motions between observed and stochastically predicted has been

performed for recently reported small magnitude events, which were recorded at the country‟s

broadband network.Stochastic predictions with the Brune‟s point source model of a 10 MPa (100

bars) stress drop, exhibited a good compliancy with observed records. Finally, a scenario investigation

in the local context was undertaken to identify expected ground motions which can be induced by

possible major events.

Keywords:Sri Lanka, Seismic sources, Stochastic simulation, Ground motions





8

SECM/13/09

EFFECTS OF FOOTFALL INDUCED VIBRATIONS ON COMPOSITE AND CONCRETE

FLOORS

E.P. De Silva1, L.T. Leong

2, M.P. Anwar

3, W.Elleithy

4

1Department of Civil Engineering, University of Nottingham, Malaysia

Telephone:+6017215-5229; Fax: +6038924-8001



Telephone:+6038924-8181; Fax: +6038924-8001

E-mail:[email protected]


Telephone:+6038924-8618; Fax: +6038924-8001



Telephone:+6038924-8617; Fax: +6038924-8001


Abstract

Although human induced vibrations are not a crucial threat to the structural integrity of a floor system,

vibrations in different flooring systems are important serviceability considerations in the design of many

structures. In past years, most of the vibration problems were dealt with by satisfying traditional deflection

criteria. More efficient design methods andthe use of light-weightconstruction materials resulted inhigher

vibration and therefore acceleration to a level of human discomfort.This paperpresents a comparative study

of the effect of different parameters of flooring system, e.g., floor span, slab thickness and the aspect ratio of

composite and concrete flooring systems on the dynamic behaviour when subjected to footfall induced

loads. Finite element modelling of the different flooring systems was used for the analysis.Dynamic

response in terms of deflections and accelerations were evaluated for each type of slab and compared.

Keywords: Footfall, dynamic response, composite floors, finite element modeling









9

SECM/13/10

HOLLOW CORE SLABS IN FLOOR CONSTRUCTION

R.C. Loganathan

Perigon Lanka Pvt Ltd, 32C Dickmans Road, Colombo 5, Sri Lanka

Telephone +94 777272360; Fax +94 11 2505940

Email: [email protected], [email protected]

Abstract

Today there is a great need for sustainability in construction activities. One tenth of the world‟s

economy goes towards building and managing housing and commercial property. This sector accounts

for more wood, minerals, water and electricity than the remaining 90 per cent of the economy.

Therefore it is essential to have a fresh view on how we carry out our construction activities.

Pre-stressed Solid and Hollow Core slabs are becoming increasinglypopular as the construction

industry attempts to minimise its impact on the environment. Hollow Core slabsbecame more popular

due the amount of concrete used is reduced without significantly altering the capacity of the element.

In presenting this paper and having personnel experience in the installation of hollow core slabs, I

have tried to address the following issues.

1. Importance of Hollow Core Slabs in Sustainable Construction industry

2. Advantages

3. Construction problems

4. Tolerances

5. Frames and Stability

6. Selecting a Slab

7. Penetrations & Fixings

8. Detailing

9. Load testing

Basically this paper covers more on practical aspects from the planning stage to execution. I have not

touched on the actual design of the hollow core slabs as it has to be carried out by a specialist

structural engineer with experience in pre-stress design. However I have outlined few basic guidelines

toselect a HC slab.

Keywords: Hollow Core slab, Sustainability, Construction Industry, Advantage, Detailing.



10

SECM/13/11

ADAPTIVE CONTROL OF FLUTTER AND BUFFETING IN LONG SPAN SUSPENSION

BRIDGES: A CASE STUDY ON AKASHI KAIKYO BRIDGE

M.P. Anwar1, H. Yamada

2, H. Katsuchi

3, J. Jayaprakash

4

1Department of Civil Engineering, The University of Nottingham, Malaysia.

Telephone:+603-8924-8618; Fax: +603-8924-8001


2Department of Civil Engineering, Yokohama National University, Japan.

Telephone:+81-45-339-3006; Fax: +81-45-339-3009


3Department of Civil Engineering, Yokohama National University, Japan.

Telephone:+81(45)339-4243; Fax: +81-45-339-3009


4Department of Civil Engineering, The University of Nottingham, Malaysia.

Telephone:+603-8725-3484; Fax: +603-8924-8001


Abstract

The effect of self-excited forces such as flutter and buffeting makes the control of the suspension bride

vibration a uniqueproblem since any externally applied control force will change the self-excited forces and

hence the entirebridge response. Therefore, a control method capable to cope with the continuously

changing process willbe required. Numerous active and passive control methods have been developed since

the evolution of suspension bridges. The present study will introduce the application of adaptive control

method that hasnot so widely been used for civil engineering applications. An adaptive controller is a

controller that modifies its behavior in respect to the change in the dynamic system and the characteristics of

the disturbance by online system identification. Unlike the conventional active controller, which has single

loop of the normal feedback, the adaptive controller has an extra loop for parameter adjustment depending

on the change in the process dynamics. Adaptive pole placement method using theself-tuning regulator was

used in the present study to control the vibration of Akashi Kaikyo Bridge in Japan. First the complex

eigenvalue analysis was carried out for the bridge and then the adaptive control algorithm using the self-

tuning pole placement was used to minimize or eliminate the undesirable vibrations.

Keywords: Adaptive control, flutter, buffeting, system identification, pole placement.








11

SECM/13/12

DESIGN AND CONSTRUCTION OF DAGABA AT MAHAMEWNAWA - KUNDASALE

J. U. Sanjeewa Perera

Central Engineering Consultancy Bureau, Sri Lanka

Telephone: 094 071 4488248


Abstract

This paper describes the design and construction of Dagaba (Pagoda) at Mahamewnawa meditation

centre, Kundasale, Sri Lanka. Planning, Estimation and design considerations are explained. Analysis

and Design of concrete shell structure with limiting tensile stresses in concrete is critically looked.

Design of circular strip foundation, ”Pesa walalu”( Ring beam) at different levels, “Hatharas

Kotuwa”(first square chamber), “Dewatha kotuwa” (second circular chamber), “ Koth Karalla” (cone

structure) and “Kotha” (pinnacle) with respect to the ancient Dagab‟s also explained. Importance of

form work and their detailing is presented with Innovative design of movable formwork support truss

and the accuracy of maintaining the radial distance to inner wall of shell. Estimation of the Bill of

Quantities and method of payment mode to uninterrupted cash flow takes major part of timely

completion of the project. Proper design and detailing, the contractor‟s ability and technological

knowhow and the cooperation with the client – contractor in a design and built contract are also

explained.

It should be noted that although the methods of analysis outlined in this paper can also be applied to

similar type shell structures (ie Pagodas), but essentially the bearing capacity of the particular

foundation have to be investigated accordingly.

Keywords: Shell, Ring beam, Foundation, Form work, Bering capacity

12

SECM/13/13

EXPERIMENTAL STUDY OF SHEAR RESISTANCE OF SRC COLUMN CONSTRUCTED

BY SIMPLIFIED METHOD

A. Kitano1

1Department of Architecture, Maebashi Institute of Technology, Japan.

Telephone: +81-27-265-0111; Fax: +81-27-265-7341


Abstract

The number of steel and reinforced concrete(SRC) structures being constructed in Japan has declined. This

is because of their complicated structure design and the large number of processes requiredin their

construction. However, their ductilityis higher than that ofreinforced concrete structures. For example, the

damage to SRC structures was minimal in the Southern Hyogo prefecture earthquakeof1995. Research into

composite structures, which could deal with a various demand, are thereforepopular. For example, a number

of studies have been conducted on RCcolumn-steelbeam structures that place the member in

dynamicallyeffective places.

We carried out experimental studiesto develop a new steel and concrete structural system that is easier to

constructthan SRC structures and withearthquake resistance performance equivalent to that of SRC

structures. The new structure is concrete encased steel(SC) without the reinforcing bar used in SRC

structures and including weldedwire mesh.

The following results were obtained.Construction method using the weldedwire mesh for the column

was easier than that for conventional SRC structures.An equivalent shear strength can be expected

assuming the SC structure has asteel cross section equal to that of the SRC structure. The steel cross

section of the proposed SC structure should be larger than that of the SRC structure and the steel

bears the flexural capacity.

Keywords: Concrete encased steel column, Steel and reinforced concrete structure, Shear strength,

Shear resistance, Construction method

13

SECM/13/14

NEW APPROACH TO EVALUATE INITIAL SETTING TIME OF FRESH CONCRETE

R.R.C.Piayasena1, P.A.T.S.Premerathne

2, B.T.D.Perera

3 S.M.A Nanayakkara

4

1Department of Civil Engineering, University of Moratuwa

Telephone: 0719035240








Abstract

According to ASTM 403C, initial setting time of concrete is measured based on penetration resistance

of mortar sieved from concrete and it is taken as the time to achieve a penetration resistance of

3.5MPa. This penetration resistance is an arbitrary value. Therefore actual initial setting time may

vary from this. The objective of this research is to find a practical value for the initial setting time of

concrete which is related to the formation of cold joints in concrete structures.

This was done by evaluating the mechanical properties (tensile strength and shear strength) of a

purposely made cold joint. Range for initial setting time was identified based on change of

mechanical properties of joints made by placing concrete with varying time delay between two layers.

Penetration resistance corresponds to this identified time range was evaluated.

As another approach, the ultrasound pulse velocity was used to monitor the change of stiffness of

fresh concrete with time. Time corresponds to changing point of ultrasound pulse velocity can be

considered as the initial setting time since it corresponds to change of stiffness of fresh concrete.

Although these two methods are effective to identify the initial setting time of concrete, those are not

possible to use as field tests. Therefore, an attempt was made to obtain a simple test method with

repeatability and reproducibility. As a field test, poker vibrator can be inserted into concrete with

predefined time intervals and identified the earliest time at which poker leaves a trace on the fresh

concrete surface. This time can be considered as the initial setting time of concrete.

Based on the test results of experimental investigations (mechanical properties test and ultrasonic test)

it was found that the more realistic initial setting time of concrete is the onset time of the penetration

resistance of mortar. This was further verified by the field test where the initial setting time is

considered as the latest time that a vibrating poker can be inserted into the concrete and removed

without leaving a significant trace.

Keywords: cold joint, initial setting time, ultrasonic pulse velocity

14

SECM/13/15

DESIGNING AND DETAILING OF CONCRETE ROOF SLABS WITH DRAINAGE AND

WATERPROOFING SYSTEMS

S. Abarna1, D.T. Rajasekaran

2

1 State Engineering Corporation, Sri Lanka.

Telephone: 079143166; Fax: 0112-434944


2 State Engineering Corporation, Sri Lanka.

Telephone: 0714-319055; Fax: 0112-434944


Abstract

Large number of multi storyed buildings in Sri Lanka are designed and constructed with reinforced

concrete roof slabs and beams arrangement. It has been observed that some of the roof slabs are not

properly detailed to provide an adequate slope and also the slopes are not correctly oriented to have a

perfect storm water drainage system. The other important aspect is to specify an appropriate

waterproofing system.

Structural designers leave the selection of waterproofing system and the drainage arrangement to the

specialized contractor. However it is the responsibility of the structural design engineers to ensure

that the roof slab is adequately designed to withstand the anticipated load and to incorporate the

details of drainage arrangement and waterproofing system.

This paper illustrates the detailing arrangement for storm water disposal for various situations in the

slab and the waterproofing system that should be used with appropriate arrangements for roof slabs,

downpipes, gutters and guard walls. It also gives some guidance for heat insulation of the roof slab

with relevant properties that are suitable for our local condition.

The information given in the paper is based on past experience and the design, detailing work done in

our organization.

Keywords: Reinforced concrete roof slabsand beams, Adequate slope, Drainage arrangement,

Waterproofing system, Anticipated load


15

SECM/13/16

THE CURRENT CONSTRUCTION SAFETY APPLICATIONS AND ROLE OF INDUSTRY

PROFESSIONALS FOR SUSTAINABLE IMPROVEMENT

M. Gunduz1, A.E.Korkut

2

1Department of Civil Engineering, American University of Sharjah, UAE.

Telephone: +971 515 4907; Fax: +971 515 2200


2Turkish Ministry of Labor and Social Security, Turkey

Telephone: +90 312 2966000; Fax: +90 312 2155028


Abstract

The current construction safety level in Turkey is continuously improving. This paper will focus on

what has been carried out in Turkey and what is planned ahead. The role of parties in construction

industry will be presented. The past and ongoing efforts in Turkey will be summarized. The paper will

also focus on EU-funded projects and their effects in Turkish construction industry. The effect of

management systems, easily applicable methods to SMEs will be briefly introduced and their effects

for the last few years will be presented. Graphical presentations on improvements will be provided.

There are still many things to be carried out to bring Turkey‟s construction safety level to worldwide

standards. Some strategies will be listed as recommendations for future works.

Keywords: Construction safety, sustainability, safety management systems




16

SECM/13/17

POTENTIAL DESIGN IMPLICATIONS ON INDOOR ENVIRONMENTAL QUALITY

IMPROVEMENTS IN GREEN BUILDINGS

Harshini Mallawarachchi1, Lalith De Silva

2, Rameez Rameezdeen

3

1Department of Building Economics, University of Moratuwa, Sri Lanka

Telephone: 071-2201158; Fax:0112650738



Telephone: 071-8065129; Fax:0112650738


3University of South Australia, Australia


Abstract

Buildings have a significant and continuously increasing impact on the environment because they are

responsible for a large portion of carbon emissions and use a considerable number of resources and

energy. Further, it also affects the health and wellbeing of the occupants. The impacts of buildings on

the quality of the indoor environment and the general environment are determined by numerous

factors during design, construction, operation, maintenance, and ultimate disposal of a building.

However, designers only control the intended construction; builders, users, managers, and others

determine many building factors that determine indoor environmental quality. However, designers can

improve the likelihood a building will be healthy with respect to indoor environmental quality by

anticipating the use of the building and providing for it in their designs. Consequently, the green

building movement has emerged to mitigate these effects and to improve the building construction

process. Hence, buildings are increasingly designed or required to be „green‟ in recent years, giving

the quality of the indoor environment new importance. Modern green work environments would

benefit from the modifications of indoor environmental conditions that can potentially increase user

satisfaction and work productivity. Therefore, several green building assessment tools have been

applied worldwide namely, Leadership in Energy and Environmental Design (LEED), Building

Research Establishment Environmental Assessment Method (BREEAM), Comprehensive Assessment

System for Building Environmental Efficiency (CASBEE), Green Star and GREENSL® Rating

System in Sri Lanka, in facilitating high quality indoor environment. These techniques were evaluated

in this paper in order to identify green building design implications which make sure the indoor

environmental quality improvements in green buildings. Thus, various indoor environmental quality

factors relate to temperature and humidity, acoustic, ventilation, indoor air quality, day lighting and

lighting quality, thermal comfort and access to views have been considered.

Keywords: Green building, Design implications, Indoor environment quality, Green assessment tools



17

SECM/13/19

ASSESSMENT OF DIFFERENT ASPECTS OF R.C. FLAT-SLAB BUILDING OVER

NORMAL R.C. FRAME BUILDING

Mohd Rizwan Bhina1 ,Arnab Banerjee

2, D.K.Paul

3

1Department of Earthquake Engineering, Indian Institute of Technology, Roorkee, India.

Telephone: +917417474605



Telephone: +917417529513



Telephone:+919897065522


Abstract

Flat-Slab building is very popular from the aesthetic and architectural point of view. From functional

aspect a flat-slab building is more efficient than a R.C. frame building. So, construction of Flat-Slab

building is increasing also in high seismic zone. Sometimes international building codes remain silent

about the seismic response of flat slab buildings. In this paper the response of Flat-Slab building and a

normal symmetric R.C. frame building of same dimension have been studied for varying seismic

intensities. Static, Response Spectrum, Pushover, and Time history analysis have been performed to

assess the performance of the two buildings. The costs of construction for these two buildings have

also been compared. An extensive study on lumped plasticity model as per FEMA 356 with varying

position of plastic hinge and its effect on pushover curve has also discussed in the paper. The paper

also comments on the plastic hinge pattern.

Keywords: Flat slab building, Lumped plasticity model, Plastic hinge, Pushover analysis, Time

history analysis, Performance of flat slab and typical R.C. building




18

SECM/13/20

STRENGTH GRADING OF INDIGENOUS TIMBER

H.E. Mallikarachchi1, K.Baskaran

2

1Department of Civil Engineering, University of Moratuwa, Sri Lanka

Telephone: +94-0719125972



Telephone: +94-11-2650567(Ext.2010); Fax: +94-11-2651216


Abstract

Timber is the only building material on earth which is naturally renewable, recyclable and leaves a

lighter foot print than any other. In its production, the embodied energy in wood is a fraction of

energy required to produce almost any other building material. Timber structures built in Sri Lanka

centuries ago are still standing passing the test of time. But still there is no standard grading available

for indigenous timber materials in Sri Lanka which has limited their use as a structural material.

Compared to many other countries where most of single or two storey houses are totally built out of

timber, Sri Lanka has either failed to recognize or underestimated its potential to be used as a

structural material.

Although the mechanical properties of structural steel and concrete have been thoroughly studied and

well documented at production stage, there exists no comprehensive data available in Sri Lanka

describing mechanical properties of structural timber. Therefore, this research contributes to fill the

above gap in timber construction industry by selecting four common timber species in Sri Lanka,

namely Jack, Neem, Coconut and Palmyrah.

Although perfect visual grading according to standard codes could not be carried out, all test pieces

were visually inspected for any strength reducing characteristics before mechanical tests. Static

bending test, tensile test and compression test were conducted to classify flexural strength, tensile

strength parallel to grain, compression strength parallel to grain and elastic modulus. Moreover,

density and moisture content were measured along with that. Mechanical properties of Jack, Neem,

Coconut and Palmyrah were assessed and characteristic strength and stiffness values were determined

by statistical analysis. Finally, each timber is classified into strength class according to European

strength class system defined in BS EN 338: 1995. Further tests are recommended to carry out to

confirm grading, since timber vary in properties with origin, life time etc.

Keywords: Strength Class, Visual Grading, Machine Grading


19

SECM/13/21

ANALYTICAL EVALUATION OF ASYMMETRIC HYSTERETIC BEHAVIOR OF

UNBONDED POST-TENSIONED PRECAST CONCRETE BEAMS WITH ENERGY

DISSIPATING CONNECTIONS

T. Koshikawa1, H. Kadowaki

2 , M. Matsumora

3

1Faculty of Engineering, Hokkaido University, Japan.

Telephone: +81-11-706-5333; Fax: +81-11-706-5333


2Graduate School of Engineering, Hokkaido University, Japan.

Telephone: +81-11-706-5333; Fax: +81-11-706-5333


3Graduate School of Engineering, Hokkaido University, Japan.

Telephone: +81-11-706-5333; Fax: +81-11-706-5333


Abstract

Recently, energy dissipating beam-column connections for unbonded post-tensioned precast concrete frame

structures have been developed. These connections consist mainly of beam-end yielding or friction dampers

to provide energy dissipation and unbonded post-tensioning tendons to produce a self-centering response.

Although several experimental and analytical studies on frame structures with these connections have been

conducted to investigate and validate their structural behavior, most of them deal with the case where each

beam has connections with the same details at both beam-ends. When a beam‟s connection details are

different (e.g. a connection with dampers at one end of the beam and one without dampers at the other), the

beam‟s behavior becomes asymmetric. This affects the response on each side of the connections. To

investigate the asymmetric behavior of a beam spanning two adjacent energy-dissipating connections, we

develop an iterative analytical procedure for predicting hysteretic responses of the beams and connections.

The procedure is based on sectional analyses to predict moment versus gap-opening rotation relationships

for each connection and on the concept of a “connected two-cantilever beam model”to satisfy global beam

displacement conditions. Parametric analysis of the influence of variations in damper arrangements and the

characteristics of each connection on hysteretic behavior is conducted using the analytical procedure. The

results show that the hysteretic energy dissipation capacity of the beam can be related to the sum of the

moment contributions due to the yield or friction forces of the dampers, and that in some damper

arrangements, residual rotations due to concrete damage at the beam-end may occur even if the beam‟s

residual displacements are negligible.

Keywords: Unbonded post-tensioning, Precast/prestressed concrete, Asymmetric behavior, Energy

dissipation, Beam-end damper


20

SECM/11/22

GUSSET PLATE CONNECTION ANALYSIS AND DESIGN

Shervin Maleki , Ahmad Monjezi

Department of Civil Engineering, Sharif University of Technology, Tehran, Iran

Telephone: +98-21-66164251; Fax:+98-21-66014828


Abstract

Braced steel frames are one of the most economical structural systems for resistance against lateral

loads such as earthquake and wind. The gusset plate connects the brace to the beam and column and

transfers the forces down to the foundation. The design of gusset plate connections has been studied

by many researchers. Currently, the Uniform Force Method (UFM) is accepted as a viable tool in

determining the connection forces. In this paper, by using an accurate 3D finite element model of the

connection, the behavior of gusset connection is explored. Parameters such as, brace size, brace angle,

gusset size, gusset end distance are varied to capture the true behavior. The results for connection

forces in each case are checked against the UFM method. Results show that UFM could not predict

the connection forces accurately in some cases. In these cases, a modification to the UFM is proposed

for design purposes.

Keywords: Steel connection, Gusset, Brace, Finite element method, Uniform force method

21

SECM/13/23

STRENGTH OF ANGLE SHEAR CONNECTORS

Shervin Maleki , Marzieh Khalilian

Department of Civil Engineering, Sharif University of Technology, Tehran, Iran

Telephone: +98-21-66164251; Fax:+98-21-66014828


Abstract

In many parts of the world angle and channel shear connectors are used instead of studs due to ease of

welding and availability. However major steel design codes do not address the strength of angle

connectors. In this paper, a nonlinear finite element model is proposed to simulate the push-out test of

angle shear connectors embedded in a solid concrete slab. The results obtained from the finite element

analyses are verified against existing experimental results. By using this nonlinear model, a

parametric study is performed to investigate the effects of variations in angle dimensions, concrete

strength and steel yield stress. Based on the parametric study, a formula is proposed to predict the

ultimate strength of angle shear connectors.

Keywords: Shear connectors, Composites, Angles, Finite element method

22

SECM/13/24

LINKING MATERIALS, STRUCTURAL PERFORMANCE AND QUALITY

MANAGEMENT OF ASPHALT PAVEMENTS

Rajib Mallick1, A.Veeraragavan

2

1CEE Department, Worcester Polytechnic Institute (WPI) 100 Institute Road,

Worcester 01609 United States

Fax: +15088315808


2IIT Madras, India


Abstract

Road pavements constitute one of the most important components of a country‟s infrastructure. The

building of an asphalt pavement consists of three major steps – selection of materials and their

characterization, structural design, and finally construction of the pavement with adequate quality control.

The linkage between properties of the pavement component layer materials, structural performance of the

constructed pavement and the quality management is often overlooked. Specifications for material selection,

construction and quality control in most cases could be improved significantly on the basis of rational and

practical basis. The objective of this paper is to illustrate the effect of variability in materials and mix

properties on the structural performance of a typical asphalt pavement, and a method to consider this

dependence as a basis for developing rational specifications for quality management during construction.

The scope of work reported in this paper consists of identification of appropriate models relating mix

properties to stiffness, stiffness to structural response and finally, response to life of pavements, through

Monte Carlo simulations, and evaluating the effect of the difference in the properties of the pavement

materials on the life of pavements. Finally, a rational method of determining pay factors for proper quality

management of pavement construction is provided. The paper discusses the current shortcomings of the

various models, evaluates the sensitivity of performance of pavement structures to material properties, and

presents the concept of reliability as part of quality control specifications for asphalt pavement construction.

Keywords: pavement-desig, dynamic modulus, fatigue, rutting



23

SECM/13/25

ANALYSIS AND DESIGN OF IRREGULAR TALL BUILDINGS IN HONG KONG BY A

STRENGTH-BASED DESIGN APPROACH

R.K.L. Su1, W.C. Keung

2, T.O.Tang

3, D.T.W. Looi

4

1Department of Civil Engineering, The University of Hong Kong, China.

Telephone: +852 2859 2648; Fax: +852 2559 5337


2 Department of Civil Engineering, The University of Hong Kong, China.

Telephone: +852 2859 2657; Fax: +852 2559 5337



Telephone: +852 2859 2665; Fax: +852 2559 5337



Telephone: +852 2859 2657; Fax: +852 2559 5337


Abstract

The development of design principles for tall buildings for any level of seismic hazard is much in

need because the current codes of practice worldwide still do not fully provide the required guidance.

The availability of design experience and guidance for low-to-moderate seismicity regions is

especially scant. As buildings become taller, wind effects increase and earthquake effects decrease.

Hong Kong, situated in a region of high typhoon and low-to-moderate seismicity, with an abundance

of tall buildings, may offer a unique experience in the design of tall buildings for the effects both of

wind and seismicity. This paper presents a strength-based design approach for the seismic design of

irregular tall buildings in low-to-moderate seismicity regions, and provides a Hong Kong example

with a transfer plate as an illustration. It is found that the example building, which has satisfactory

performance under strong typhoon conditions, is capable of meeting force and displacement demands

during rare earthquakes, using the proposed softened stiffnesses, expected strength factors and inter-

storey drift ratios for structural members. Consideration is also given to the effects of a massive and

stiff transfer plate in the building as regards the displacement responses, any abrupt change to the

inter-storey drifts, as well as shear concentration in the shear walls. These effects are confirmed but

found not to be critical in the example building.

Keywords: Irregular tall buildings, Low-to-moderate seismicity regions, Strength-based design

approach, Three-dimensional finite element analysis, Response spectrum analysis





24

SECM/13/26

QUALITY MANAGEMENT OF PUBLIC SECTOR BUILDING CONSTRUCTION - A CASE

STUDY

A.Ranasinghe

District Engineer‟s Office, Southern Provincial Engineering Service, Sri Lanka

Telephone: 071-5345946; Fax:-041-2222386

[email protected]

Abstract

Quality plays vital role in construction industry. It doesn‟t mean out-word appearance of the building

but entire construction process need to be maintain quality assurance system to achieve better result.

Specially in public sector constructions are concerned mainly education sector and health sector are

prominent and view of the general public is not very satisfactory. Larger amount of money

contributed by the government budget each year for infrastructure development of health and

education so it is a duty of engineering professional to deliver good quality output for the benefit

general public. How to develop the mind-set of all relevant parties including contractor, client

consultant and stake holders adaptation to relevant standards. The main idea of this research is to find

out factors affecting to public sector construction and how to achieve adequate quality through the

standard specification based on the ICTAD buildings specification. An also this study is carried out as

a case study based on Matara District public sector building construction.

It is found that very less attention was paid to the public sector building at their construction stages.

Few years of completion there are various complains were aroused. Specially durability , poor quality

bad supervision and usage of substandard material. Were greatly affected. Questionnaire survey was

also proved that all parties expectative is to construct better quality building. Without having adequate

quality we can‟t fulfill the people needs. As a citizen of the country we have dual responsibility as an

Engineer as well as stake holders to do the better job for the betterment of the country. Main

responsibility of ours is to change attitude of our staff, Contractor staff as well as stake holders staff to

achieve successful goal. Some says corruption, negligence and political interferences are the most

controversial issues related to public sector. But our target is to deliver good service to the country to

achieve accountability, transparency and follow the principle of rule of law for the achievement of

good governance.

No of methods were used to test the quality achievement under this study. Material testy method,

literature survey, questionnaire survey, interviews, supervision, observation etc.In addition to that

client, contractor, consultant and stake holder partnerships also taken into consideration. This study

would held to develop the quality assurance system of the department in following way

implementation of quality assurance system, development of attitude of all parties, empowerment of

technical skills and development of contractors and technical staff to delivering better out put.

Attitudinal development ethical and competent staff were the final outcome of the proper.


25

SECM/13/27

CYCLIC TESTING OF A STEEL FRAME

S. R. Satish Kumar1, C. Arunsekhar

2

1Department of Civil Engineering, IIT Madras, Chennai, India.

Telephone: 91-44-22574287



Telephone: 91-44-22574287


Abstract

Performance based plastic design is considered to be an improvement over the traditional force-based

design. However, practical implementation of the procedure requires information on the force-

displacement characteristics of the frame which in turn depends on the moment-rotation relationship

for the cross-section. The usual method is to adopt plastic cross-sections which can be assumed to

have an elastic-perfectly-plastic relationship and evaluate the performance based on the maximum

deformation sustained. However, such an approach ignores the low-cycle fatigue effects which tend to

cause strength and stiffness degradation. These effects depend on the ability of the sections and

connections to dissipate energy by hysteretic action. In order to understand these effects cyclic test

was conducted on a pinned base two storey steel frame designed to develop plastic hinges in the

beams. The beams were made up of cold-formed rectangular hollow beam (RHS) sections and the

columns were hot rolled I-sections. Lateral load was applied cyclically in the form of displacement at

top storey level. The beam ends developed local buckling which increased progressively with increase

in the amplitude of cycling leading to the formation of a global collapse mechanism. The test results

were compared with pushover analysis deviations between the two are quantified and an improved

method based on the cyclic envelope curve is shown to give better results.

Keywords: cyclic test,rectangular hollow sections, local buckling, ductility, energy dissipation capacity,

bolted connections, pushover analysis.


26

SECM/13/28

STRENGTH AND DUCTILITY OF STEEL FRAMES WITH SLENDER WEBS

Nibedita Sahoo1, S. R. Satish Kumar

2


Telephone: 91-44-22574287



Telephone: 91-44-22574287


Abstract

Steel built-up I sections, composed of plates with high width-to-thickness ratios (slender sections), are

commonly used in pre-engineered buildings under the premise that the design is governed by wind

especially in lower seismic zones. However, in the event of a severe earthquake, the sections are

susceptible to local buckling and may exhibit a non-ductile behavior. Therefore it is imperative to

check the performance of such structures under the maximum credible earthquake. As a first step

towards this objective, it is necessary to evaluate the post-buckling strength and ductility of such

sections. In this paper, a Finite element model is developed to analyze the inelastic post-buckling

response of semi-compact and slender plates. The results are summarized in the form of empirical

formulae giving the strength and ductility as a function of plate width-to-thickness ratio. The

information can be used to predict the moment-rotation curves for I-sections with slender webs.

Keywords: width-to-thickness ratios, slender elements, local buckling, ductility, moment-rotation

curves, portal frames.


27

SECM/13/29

PHYSICAL ACTIVITY LEVEL OF GENDER IN PADDY FARMING: A CASE STUDY OF

PAVATKULAM MAJOR IRRIGATION SCHEME IN THE VAVUNIYA DISTRICT

T. Jeyaruba1, S. De Silva

2,D.A.N. Dharmasena

3

1Postgraduate Institute of Agriculture, University of Peradeniya


2Department of Agricultural Extension, Faculty of Agriculture, University of Peradeniya


3Dept. of Agricultural Engineering, Faculty of Agriculture, University of Peradeniya


Abstract

Paddy cultivation is a major source of livelihood, employment and nutrition. Females play an

important role in paddy cultivation, their contribution is unrevealed and or undervalued. This

research, investigates the physical activity level of gender in paddy farming of three major ethnic

communities; Sinhala, Tamil and Muslim in a selected major irrigation scheme in the Vavuniya

district. A total number of 156 farm families, including 63 Sinhalese, 63 Tamil and 30 Muslim were

proportionately and randomly selected through stratified sampling technique. A combination of

Participatory Rural Appraisal (PRA) tools and a questionnaire survey were used to collect data during

the 2010/2011 Maha season. The total energy spent by different individuals for paddy cultivation and

household activities per day was calculated, using the BMR (Body Metabolic Rate), energy

expenditure and PAL (Physical Activity Level) equations. Household reproductive activities are

mostly done by females (93%). The involvement of males in paddy cultivation is higher (71%) than

females. In the Sinhala community, involvement of females in paddy cultivation is one and half and

three times higher in comparison with the involvement of females in Tamil and Muslim communities,

respectively. Females those who involve in paddy cultivation in their own fields or work as labourers

in other paddy fields in addition to household work, are engaged in Extreme Activity according to

PAL models.Females spend an average energy of 1486 kcal per day for household work and 45% of

the females spend 2372 kcal per day as they are involved in both household work and income

generating activities within the homestead. Males spend 1409 kcal per day as the average energy for

cultivating three acres of paddy land as a fulltime farmer. Females are overworked due to taking care

of household activities in addition to helping the farming and other income generating activities with

their spouses. Therefore, greater attention needs to be paid on sharing the household activities

between males and females in the farming communities.

Keywords: Energy, Gender, Household activities, Irrigation, Paddy farming



28

SECM/13/30

CHARACTERISTICS OF CONCRETE CONTAINING NANO-SILICA AND RECYCLED

CONCRETE AGGREGATE

B.B. Mukharjee1, S.V. Barai

2

1 Research Scholar, Department of Civil Engineering, Indian Institute of Technology Kharagpur,

India,

Telephone: +918900164776


2Professor, Department of Civil Engineering, Indian Institute of Technology Kharagpur, India,

Telephone: +91 - 3222 - 283408


Abstract

The use of concrete in construction industry increases too many folds in recent years, which lead to the

increase in the consumption of natural aggregates as aggregates are the largest component of concrete. The

vast use of concrete is mainly accountable for depletion of natural resources since aggregates are primarily

produced from nature. Simultaneously, huge amount of concrete wastes are generated due to demolition of

old structures and adequate number of landfills are not available to mitigate such growing demand of

dumping sites. Therefore, the efficient utilization of waste concrete is to produce aggregates from concrete

wastes and use those aggregates in place of natural aggregate during production of concrete. However, it is

well documented in literature that the properties of the concrete procured with recycled concrete aggregates

have inferior to normal concrete.

The recent advances in nanotechnology persuade researchers to develop new materials of the order of nano-

scale and apply those materials in cement-based products to modify their properties. Among all the applied

nano-materials in cement and concrete, nano-silica is most effective in modifying the parent products on

nano level. Previous studies in the area of application of NS in cement and concrete products confirmed that

NS enhances the strength of cement paste and mortar along with the densification of microstructure.

The aim of the present study is to investigate the effects of addition of colloidal Nano-silica on the

mechanical and non-destructive parameters of recycled aggregate concrete. This paper reports the results of

compressive strength test , tensile strength along with nondestructive test results of the concrete with three

(0.75, 1.5, and 3) different percentage of Nano-silica. The results of this experimental study reveal that the

incorporation of Nano-silica improves the both compressive and tensile strength of recycled aggregate

concrete and there is a significance improvement in nondestructive test results are observed, which signifies

about the overall improvement of quality of concrete.

Keywords: Colloidal nano-silica, Nondestructive test, Recycled aggregate concrete, Pozzolanic effect




29

SECM/13/31

FINITE ELEMENT MODELING OF REINFORCED CONCRETE BEAMS

STRENGTHENED FOR FLEXURE WITH CARBON FIBER REINFORCED POLYMERS

N.Prakash1, C. S. Lewangamage

2, B.C.R Jayanath

3

1Department of Civil Engineering, University of Moratuwa, Sri Lanka.




Telephone: +94-11-2650567 (Ext. 2014); Fax: +94-11-2651216


3University of Moratuwa Sri Lanka


Abstract

Aging of reinforced concrete structures is a major concern in the recent past and strengthening these

structures using externally bonded Carbon Fiber Reinforced Polymers (CFRP) is a promising method.

Prediction of behavior of CFRP strengthened concrete members using finite element method (FEM)

has become increasingly popular due to the advancement in the computational power and limited

material resources. A three dimensional nonlinear FE model for rectangular reinforced concrete beam

strengthened with externally bonded CFRP has been developed using ANSYS and calibrated using

experimental results of CFRP strengthened beam in flexure.ANSYS FE model shows good agreement

with the experimental results.

Keywords: Beams, strengthening, Flexure, CFRP, Finite element modeling.




30

SECM/13/32

EXPERIMENTAL STUDY ON REINFORCED CONCRETE COLUMNS PARTIALLY

CONFINED WITH CARBON FIBER REINFORCED POLYMER (CFRP)

C.S.Lewangamage1, C.K. Rankoth

2, D.M.D.N. Sanjeewani

3


Telephone: +94-11-2650567(Ext 2014); Fax: +94-11-2651216



Telephone: +94-77-2548705


3Central Engineering Consultancy Bureau, Sri Lanka

Telephone: +94-77-5536221


Abstract

The requirement of strengthening of reinforced concrete structures may emerge not only due to timed

degradation but also due to various reasons like construction faults, increased loads and changes in

utilization purpose etc. Rehabilitation of reinforced concrete structures using Carbon Fiber Reinforced

Polymer materials is recognized as a very effective retrofitting method

The current practice on strengthening reinforced concrete columns with external CFRP jacketing is to

provide full wrapping all over the column with less care on the required strength increment. As CFRP

is a costly material, providing partial wrapping may be a viable option for cost reduction rather than

providing full confinement.

An experimental study was carried out with 17 specimens to study the partial confinement effect. The

test specimens consist of 6 plain concrete columns with 3 control specimens and 3 fully confined

columns. 11 reinforced concrete columns with 3 control specimens, 3 columns with full confinement

and 5 columns with partial confinement. Two wrapping patterns were used for partially confined

columns with 75mm and 50mm laminate width, keeping the volumetric ratio of CFRP constant to

study the effect of wrapping pattern and jacket location for strength and ductility increment.

The results of experimental study revealed that the load carrying capacity increment for fully wrapped

reinforced concrete columns were 100% while for plain concrete columns it was 47% and for partially

confined columns,the specimens with two 75mm wraps showed a capacity increment of 59% while

specimens with three 50mm wraps showed an increment of 83%. It was observed that, by only

changing the jacket location 15% ultimate load carrying capacity increment can be obtained. When

ductility increment is considered it was observed that ductility increment is proportional to the

strength increment.

Keywords: reinforced concrete column, CFRP, partial confinement, strength, ductility




31

SECM/13/33

TRAFFIC INDUCED VIBRATION EFFECTS ON PEDESTRIANS ON STEEL BRIDGES IN

SRI LANKA

(A CASE STUDY)

M.A.J.D.Karunaratne1, C.S.Lewangamage

2

1The Institution of Engineers, Sri Lanka

Telephone: +94-71-6160357




Email:[email protected]

Abstract

The construction of roadways has accelerated in Sri Lanka as it is an essential factor for the economic

development of the country. Most of our existing steel bridges need to be rehabilitated to upgrade the

transportation network. The volume of traffic has increased many folds and the loads also have

increased. These have imparted serious stresses on bridges causing vibrations, and may lead to

pedestrian discomfort. This type of vibration is accentuated on steel bridges with truss girders. To

ascertain the vibration of the bridge at serviceability, site measurements need to be obtained with a view

of developing a model of the existing structure, and to validate it. Then, the model would be used to

mitigate vibration.

A case study was undertaken on the truss type steel girder bridge of three spans (each 33 m) over the

Deduruoya on Padeniya – Anuradhapura road at Kuruneegala district. This bridge has been provided

with a pedestrian walk way. The Finite Element Model (FEM) was developed usingSAP2000. Field

tests were conducted under controlled conditions with HA vehicle and vibration was measured using

very sensitive vibrometer.

The measured field data was used to calibrate the FEM model and effects on pedestrian was studied

with different vehicle speeds and the loads.

Keywords: traffic induced vibration, pedestrians, steel bridges, FEM



32

SECM/13/34

VERTICAL DISPERSION OF THE AIR POLLUTANTS OF INDOOR ENVIRONMENT IN

URBAN AREAS

K. H. D. Nayantha 1, C. Jayasinghe

2

1Department of Civil Engineering, University of Moratuwa.

Telephone:077 375 7741



Telephone: +94-11-2650567-8(Ext.2111); Fax: +94-11-2651216


Abstract

Most of the air pollution sources and sinks are present in the ground level, creating varying

concentrations in the ground level atmospheric layers and static conditions in the upper atmospheric

layers, which leads to vertical stratification of the air pollutants. Since indoor environment is a very

significant factor for the human wellbeing and is being affected by the outdoor environment to a

greater extent, study of the vertical dispersion of air quality is needed with the development of the

high rises in the urban area. This paper presents the results of the study done in the Colombo urban

region which is going to have considerable number of high rise buildings in near future.

The short term measurement of air pollutants; CO2 and PM2.5, was carried out in the selected midrise

buildings in Colombo. Considerations in building planning are suggested based on the relationship of

pollutant distribution against the floor level. Strategies to optimize the energy used for better indoor

environment in Demand Controlled Ventilation systems were also discussed. Since the vertical

stratification of the air borne pollutants in the lower troposphere is in local validity this paper

highlights the importance of study of the wind turbulence and the presence of air pollution sources

and sinks in the vicinity of the building.

Keywords: Indoor air quality, Building planning guidelines, Vertical dispersion, Carbon Dioxide,

Particulate Matter

mailto:E-mail




33

SECM/13/35

FRAGILITY CURVES FOR TSUNAMI LOADING

Isuru Nanayakkara1, Priyan Dias

2


Telephone:+94777193183




Abstract

Vulnerability to structural damage can be characterized by a fragility curve, which is expressed as the

conditional probability of reaching or exceeding a particular damage state, expressed by a lognormal

cumulative probability distribution, given a certain value of the demand parameter. Such curves have

been produced for a variety of damage states in different categories of buildings that have been

subjected to tsunami loading in different parts of the world, with the demand parameter taken as

inundation depth. Harmonization was sought across these studies with respect to the median

inundation depths and standard deviations.

Three categories of buildings were identified based on construction material; namely reinforced

concrete, masonry and timber. The median inundation depths for the complete damage state decreased

from reinforced concrete (5.4-7.3m) through masonry (2.4-2.8m) to timber (1.3-1.6m) structures as

did the standard deviations. The steeper fragility curves for the weaker structures suggest that they

display a single failure mode, probably sliding. The fairly narrow ranges above represent a number of

different studies and indicate that a common family of curves can be used in damage assessments

worldwide. Such ranges were identified for two partial damage states too.

Keywords: Fragility curves, Damage state, Inundation depth, Construction material



34

SECM/13/36

DEVELOPMENT OF NATIONAL GUIDELINES FOR SEISMIC ANALYSIS AND DESIGN

OF (ENGINEERED) BUILDINGS IN SRI LANKA

H.G.S.R.Kularathna1,C.S.Lewangamage

2, M.T.R.Jayasinghe

3

1 Department of Civil Engineering, University of Moratuwa, Sri Lanka

Telephone: +94-77-2253770








Abstract

Sri Lanka was believed to have no seismic threat compared to other natural disasters such as

landslides, floods, droughts, etc. However, it has now been realized that Sri Lanka can no longer be

considered as isolated from seismic threat following recent past events occurred in and around island.

The only available document for the purpose of seismic design of buildings in Sri Lanka is

“Earthquake resistant detailing for buildings in Sri Lanka” published by the Society of Structural

Engineers, Sri Lanka. The present study is therefore aimed to provide advice on the seismic design in

Sri Lanka and provide guidance on suitable analysis and design procedures for buildings when the

seismic consideration is explicitly warranted for a structure. The proposed guidelines in this study are

based on Euro Code 8 (EN 1998-1: 2004): “Design of Structures for Earthquake Resistance”. Euro

Code 8 was selected for this purpose because it allows national choices in defining seismic

characteristics such as peak ground accelerations, response spectra etc. in the seismic design

procedure. It also allows national choices in selecting analysis and design procedures of buildings to

resist seismic events. Therefore, this study mainly focuses on these national choices and suitable

values are proposed and discussed depending on the available limited seismic data in Sri Lanka.

Whenever there is no enough data, suitable approaches are given comparing similar seismic codes

such as IS 1893-1: 2002 and AS 1170.4: 2007.

Finally, two case studies are carried out in order to illustrate how the developed guidelines are used in

the seismic design procedure of buildings specifically in Sri Lanka. The two buildings selected for

this purpose represent buildings with high consequences of failure during an earthquake so that it

clearly shows the significance of seismic consideration in the design procedure of buildings.

Keywords: intra-plate earthquake, seismic design guidelines, Sri Lankan National Annex to EC 8





35

SECM/13/37

STUDY ON EARLY STRENGTH AND WORKABILITY OF HIGH VOLUME FLYASH AND

NANOSILICA MIXES

W.P.S. Dias1, K. Baskaran

2 , H.E. Mallikarachchi

3


Telephone: +94-11-2650567(Ext.2119); Fax: + 94-11-2651216



Telephone: +94-11-2650567(Ext.2010); Fax: +94-11-2651216



Telephone: +94-0719125972


Abstract

Global cement production contributes around 7% of annual CO2 emissions, not only through energy

consumption but also through the calcination of limestone. Hence, the use of high volumes of

supplementary cementing materials in cement mixes is considered strategic to reduce environmental

degradation. In commercial practice, the dosage of fly ash is limited to 30-40% by mass of the total

cementitious material. Larger percentages of fly ash will be more environmentally friendly but may

diminish quality. The focus of this research is to recover diminished properties of High Volume Fly

Ash (HVFA) mixes by adding nano silica. Preliminary results of the investigation such as early

strength gain and workability aspects are addressed in this paper.

Early strength (3 day and 7 day) of cement paste mixes with fly ash replacement of 30%, 50% or 70%

and 3% or 6% nanosilica were investigated to identify effect on nanosilica on HVFA mixes. The

flows of each mix were measured to get an insight about an adequate superplasticizer dosage for

sufficient workability for different proportions of flyash and nanosilica. It was found that 3%

nanosilica provided superior results than 6% nanosilica for all flyash percentages. The 70% Flyash

series exhibited lower 3 day strength even but rose considerably at 7 days. Sufficient workability can

be achieved in 3% and 6% NS cement paste mixes when superplasticizer dosage is 1200ml and

1500ml respectively per 100 kg of cementitious material.

Keywords: Fly ash,Nano silica, Early Strength, Workability



36

SECM/13/38

EVALUATION OF THE POTENTIAL FOR DELAYED ETTRINGITE FORMATION IN

PORTLAND CEMENTS

W.H.R.S. Dayarathne1, G.S. Galappaththi

2, K.E.S. Perera

3,S. M.A. Nanayakkara

4


Telephone:+94 715 565573



Telephone: +94 717 407093



Telephone: +94 772 548731



Telephone: +94 112650567; Fax: +94-11-2651216


Abstract

Delayed ettringite formation (DEF) commonly referred as heat-induced internal sulfate attack, which affects

the durability and strength of the concrete. Several researches have been done to identify the factors

governing DEF and to quantify the effect and also to provide necessary prevention methods. But most of the

factors are yet to be investigated and quantified. It is evident that when fly ash is present, the risk of

formation of delayed ettringite is low but it‟s behaviour with different types of cement have not been found

out yet.

This paper presents an evaluation of potential of DEF for different cement types available in the local

market based on “FU‟s Method. In this method, expansion of mortar bar specimens

(25mmX25mmX285mm) was monitored after specimens were subjected to specified heating and drying

cycles. The effect of aggregate phase on DEF has also been evaluated by comparing the expansion of

cement mortar and cement paste specimens. Furthermore tests have been done while replacing the sand by

using specified coarse aggregate to evaluate the effect of aggregate phase. Furthermore, the Effect of micro

cracking for the DEF has been checked by modifying the “FU” method as changing the number of drying

cycles.

It was found that Ordinary Portland Cement has higher expansion than other cement types. Furthermore it

was found that the expansion of mortar bar specimens due to DEF less when fly ash blended cement is used.

According to the test results, there is a significant effect of type of cement, presence of coarse aggregate and

micro cracks on DEF.

Keywords: Ettringite, Fly ash, Micro-cracks


37

SECM/13/39

SEISMIC ANALYSIS OF THREE LEGGED LATTICE TELECOMMUNICATION TOWERS

FOR SRILANKAN CONDITIONS

J.A. Desmond1, A.M.L.N. Gunathilaka

2, C.S. Lewangamage

3


Telephone:+ 94-71-6326266 ; Fax: : + 94-11-2651216


2Sri Lanka Telecom PLC, Colombo 01

Telephone: +94112451210; Fax: +94112331426



Telephone:+ 94-11-2650567; Fax: : + 94-11-2651216


Abstract

Mobile communication is facing an exponential growth and thousands of telecommunication towers have

been constructed in Sri Lanka to accommodate the current demand. Failure of communication tower in a

disaster like an earthquake is of major concern as this can hinder the communication needs, especially in

case of rescue operation. It also causes property damage to itself and adjacent structures. Hence, design of

telecommunication towers considering all possible extreme conditions are essential.

Sri Lanka is considered earthquake free as it is far away from earthquake prone regions and almost all local

telecommunication towers were not checked against earthquake. However designers have started to think

about earthquake design of structures as frequent tremors are recorded in recent past due to intra plate

earthquakes. Objective of this research is assessing the performance of existing three leg self-supporting

towers which were not designed for seismic loadings and find strategies for retrofitting in case of significant

adverse effect.

This paper presents the analytical results of three legged lattice telecommunication towers in different

heights under seismic loading for local conditions. Such results indicate that structural actions under local

seismic loading condition are comparatively insignificant when compared with same under wind loads for

the selected telecommunication towers.

Keywords: Three legged lattice towers, wind loading, seismic loading



38

SECM/13/40

EXPERIMENTAL INVESTIGATIONS ON BRICK AND BLOCK MASONRY WALLS

Mangala Keshava1, S Raghunath

2, K S Jagadish

3

1Department of Civil Engineering, BMS College of Engineering, Bangalore, India

Telephone:9845675201; Fax: +91-80-26614357



Telephone:9845794060; Fax: +91-80-26614357


3Department of Civil Engineering, RV College of Engineering, Bangalore, India

Telephone:9845553365; Fax: +91-80-26614357


Abstract

In India, un-reinforced masonry walls are often used as a main structural component in load bearing

structures. The load carrying capacity of masonry walls can be assessed in three ways. These

includetests on masonry constituents, tests on masonry prisms and wallette specimens and tests on

full-scale wall specimens. In the present study, two commonly used masonry units such as the

traditional bricks and concrete blocks were investigated. Tests on bricks/blocks, cement-sand mortar,

brick/block masonry prisms and full-scale brick/block masonry walls formed the basis for the

experimental investigation. The computation of the ultimate load carrying capacity of the wall was the

aim of the present study. The results thus obtained have proved that hollow concrete blocks normally

used as in-fill masonry can also be considered as load bearing elements as its load carrying capacity

was found to be high when compared to conventional brick masonry. The second aim of the study

was to understand the behavior of brick masonry walls under axial and eccentric loads. The behavior

of the walls was investigated under varying slenderness and eccentricity ratios. It was found that

higher slenderness and eccentricity ratios drastically reduced the strength capacity of the brick

masonry walls particularly for brick walls in South India.

Keywords: Brick/concrete block masonry, axial/eccentric loads, ultimate load carrying capacity



39

SECM/13/41

LABORATORY STUDY ON PREPARATION OF STABILISED MUD BLOCKS BY

DOUBLE COMPACTION METHOD

Sureka Naagesh1, S.Raghunath2, K.S. Jagadish

3

1Dept. of Civil Engineering,BMS College of Engineering,Bangalore,INDIA

Telephone: 9343045054; Fax: 91-80-26614357


2Dept. of Civil Engineering,BMS College of Engineering,Bangalore,INDIA

Telephone: 9845794060; Fax: 91-80-26614357


3Dept. of Civil Engineering, RV College of Engineering, Bangalore, INDIA

Telephone: 9845553365; Fax: 91-80-26614357


Abstract

Stabilised mud blocks are energy efficient and cost effective masonry units. They are prepared insitu

using locally available soil by mixing with stabilizers like cement or lime. Stabilized mud blocks

(SMB) offers a cost effective environmentally sound masonry system.. Stabilized Mud Blocks are

manufactured by compacting raw material earth mixed with a stabilizer such as cement or lime under

a pressure of 20-40 kg/cm2, using manual soil press such as Mardini, Tara Balram,ASTRAM, etc.

where in the compaction is unidirectional. A number of manual and hydraulic machines are available

in India. The basic principle of all the machines is the compaction of Soil to attain dense, even sized

masonry units.

This paper presents the results of an experimental study conducted to statically compact the SMB both

from its top surface and bottom surface at two different compaction conditions, viz., unequal

compaction and bidirectional equal compaction of top and bottom surface of the block. The blocks

were compacted in an UTM. The dry density, strain energy and wet compressive strength of blocks

were measured.

The results indicate that blocks compacted by bidirectional compaction method have more uniform

dry density , and require less strain energy .The variation of dry density from top surface to bottom

surface of block was about 1%.

Keywords: Stabilised mud block, compaction, soil press machines, dry density


40

SECM/13/42

RUTTING STUDIES ON THE EFFECT OF WHEEL CONFIGURATION AND

TEMPERATURE IN BITUMINOUS CONCRETE MIXUSING MODIFIED BINDERS

K.Ganesh1, H.S.Jagadeesh

2


Telephone: 9448541968, Fax: +91-80-26614357



Telephone: 9448541968, Fax: +91-80-26614357


Abstract

This paper presents the experimental studies on the rutting characteristics of Bituminous Concrete

Mixes using Conventional Bitumen (VG-10) and Modified binders, Crumb Rubber Modified Bitumen

and Polymer Modified Bitumen (CRMB-60 and PMB-70). The results will be of particular interest to

engineers in the public and private sectors with the responsibility for the design, construction,

maintenance and rehabilitation of Hot Mix Asphalt pavements. The present work is aimed at

understanding the properties of mix and the machine parameters which influence the deformation

causing ruts in flexible pavements. The rutting was caused on the beam specimens prepared in the

laboratory. The study includes the influence of different types of binders, air voids, temperature and

wheel configuration along with the applied loads on the rutting characteristics of flexible

pavements.The results were analyzed to formulate regression equations for plain and modified binders

in bituminous concrete mixes for varying temperature and wheel configuration. It was found that

modified binders have higher resistance to rutting compared to plain binders in Bituminous Concrete

mixes. PMB-70 binder performed better than VG-10 and CRMB-60 binders under the laboratory

induced applied pressures and number of passes. The results of this study clearly demonstrate the

structural behaviour of flexible pavements under varying field conditions.

Keywords: Rutting, Crumb Rubber Modified Bitumen, Polymer Modified Bitumen, Temperature, Tire

Pressure, wheel configuration


41

SECM/13/43

APPLICATION OF INFORMATION TECHNOLOGY IN THE CONSTRUCTION

INDUSTRY OF SRI LANKA

N.Puvinthan 1,I.Niyanthan

2, N.Varman

3,P.B.G. Dissanayake

4

1Department of Civil Engineering, University of Peradeniya, Sri Lanka.










Telephone: 081-2393541; Fax: 081-2388158


Abstract

The dramatic development of Information Technology (IT) over the past decades has contributed to

the development and application of IT related innovative systems in most of the industries in the

world. Construction Industry as a whole has also benefited from the development of IT. It is evident

that the construction industry differs from other industries due to its fragmented nature and the

involvement of expert knowledge, judgment and experience. Because of these complexities, the

construction industry has great potential for the application of IT.

The objective of this study is to explore the extent to which IT has been applied in the construction

industry of Sri Lanka and propose how IT could be used at different stages of a project to improve the

efficiency of the construction industry. This study was done through questionnaire surveys carried out

among contractors, consultants and construction industry professionals. The survey was carried out in

two stages with a preliminary survey followed by a detailed survey. The preliminary survey was

conducted in order to get the ideas and opinions of the construction industry professionals on the

current status of the application of IT in the construction industry. The questionnaire for the detailed

survey was prepared based on the findings of the preliminary survey.

It is expected that this study will provide an overview on the current use of IT in the Sri Lankan

construction industry and would propose necessary guidelines on how to improve the use of IT at

different stages of a project in order to improve the overall efficiency and obtain its maximum benefit

for the industry.

Keywords: Construction Industry, Information Technology








42

SECM/13/44

PREDICTION OF TEMPERATURE RISE IN CONCRETE AT EARLY AGE DUE

TO HEAT OF HYDRATION OF CEMENT

Anura Mataraarachchi1, S.M.A. Nanayakkara

2, Shingo Asamoto

3

1Department of Civil Engineering, University of Moratuwa, Sri Lanaka

Telephone: +94 71 4396036 Fax: +94 71 8801022


2Department of Civil Engineering, University of Moratuwa, Sri Lanaka


3Graduate School of Science and Engineering, Saitama University, Japan.


Abstract

Heat of hydration of Ordinary Portland Cement (OPC) is predicted considering chemical activity of mineral

components of cement, i.e. alite (C3S), belite (C2S), aluminate (C3A), ferrite (C4AF), and gypsum (CS2H).

Reactions of all these mineral components with water are exothermic. The total heat generation of cement

hydration in concrete is modeled considering many factors such as reference heat generation rate of each

mineral component, weight composition of mineral components of cement, fineness of cement, thermal

activity, interdependences of mineral components, effects of consumption free water during the hydration

process, cement content, and water content. This Multi-component hydration model is incorporated in the

finite element analysis software ANSYS using Advanced Parametric Design Language (APDL). Several

other macro programs are used to input data such chemical composition of cement, thermal properties, and

ambient temperature variations. Model is calibrated using laboratory and field data. Calibrated and verified

model can be used to predict temperature rise in a concrete element of any size at early age if the mix

proportion of concrete and chemical composition of cement are known. Furthermore, the developed

hydration model is used to investigate the effects of thermal property variations, ambient temperature

variations, lowering initial temperature of fresh concrete, most effective time of a day to start concreting,

and to propose design parameters such as temperature drop between hydration peak and ambient

temperature (T1) under local conditions.

Keywords: cement mineral components, multi-component cement hydration model, thermal analysis




43

SECM/13/45

EFFECTS OF WRAPPING METHOD ON FAILURE BEHAVIOUR OF CARBON FIBER

POLYMER STRENGTHENED FLEXURAL SYSTEMS

B.C.R. Jayanath1, C.S.Lewangamage

2


Telephone: +94-77-6732964





Abstract

Externally bonded fiber reinforced polymers (FRP) has been established as an effective technique for

strengthening concrete members. The failure behaviour of FRP strengthened reinforced members is

highly dependent on the wrapping method. Hence, the effect of wrapping method of FRP

strengthened flexural members is studied. Load carrying capacity, ductile behaviour and deflection

behaviour are studied and compared with reinforced concrete flexural members. Eight beams and

fifteen slabswere casted in Grade 30 concrete and tested in four point bending scheme. Five beams

and nine slabs were strengthened with CFRP. CFRP strain at failure was measured and compared with

existing debonding prediction expressions given in ACI 440-2R and Japanese standards. Design

moment capacities were evaluated using each code specification. Factor of safety was calculated and

compared for each case. Based on the experimentally measured debonding strain, wrapping method

based modified expression was proposed to evaluate debonding strain. A factor accounted for

wrapping method is introduced to the proposed debonding strain prediction equation in Japanese

standard.

Keywords: flexural strengthening;CFRP;debonding; wrapping methods



44

SECM/13/46

DETERMINATION OF LOAD-SLIP CHARACTERISTICS OF NAILED TIMBER JOINTS

D.M.Wijesekara1,W.A.D.Fernando

2,J.A.D.A.Wijayantha

3


Telephone: +94715934242; Fax: +94-11-2651216



Telephone: +94718013181; Fax: +94-11-2651216



Telephone: +94716388895; Fax: +94-11-2651216


Abstract

Timber is one of the most widely used and old construction materials. As it is a naturally available

material and it is very difficult to obtain large cross sections of timber such as 8”×4” or 9”×4”. So

going for built up timber beams is very essential. The beams can be built using structural glues or

nails. The glued timber beams will require higher quality control and higher workman ship while

nailed built-up timber beams require less workmanship, hence nailed built up timber beams are more

suitable for Sri Lanka. In a nailed built-up timber beam, the nailed connection is very important as the

strength of the timber beam is totally depending on the nailed connection. Slip in the nail connection

is affecting the strength of the nail connection and it is essential to determine the load-slip

characteristics of the nailed timber joints. The effect of specific gravity on the load-slip is determined

in this research using Ginisapu and Amba which are having two specific gravities.The built-up beams

are prepared and tested for the ultimate load. Then the deflection was calculated theoretically and

compared with the experimental values. The conclusion is the deviation between two values is due to

slip in the connections and the slip is tested by preparing a separate specimen.

Keywords: load-slip, built-up beams, deflection, nailed joints







45

SECM/13/47

EXPERIMENTAL INVESTIGATION OF THERMAL PROPERTIES OF CONCRETE AND

FORMWORK MATERIALS

R.Sayanthan1, K.myuran

2, S.M.A Nanayakkara

3


Telephone: +94-77-2935513



Telephone: +94-77-2266505





Abstract

The long term performance of concrete structures, especially strength and durability, are significantly

affected by the early age properties and among those, the thermal properties of concrete are of utmost

importance as temperature variation during hydration affects the rate and extent of the reaction and

hence attainable ultimate properties. Thermal gradients can also cause internal stresses which can lead

to cracking. Thermal conductance of formwork material has a significant influence on heat dissipation

to surrounding mediums such as air, soil, or water. Hence an experimental investigation was carried

out to determine thermal properties of fresh concrete in order to predict temperature distribution in

concrete elements. A thermal analysis was carried out for specific material properties and boundary

conditions, where the elements were modeled in a finite element program with assigned material

properties to verify the experimental results.

The experimental investigations have revealed that microstructural formations during the cement

hydration process, significantly affects the thermal properties of concrete. Hence the variation of

thermal properties with the degree of hydration was studied. In addition, the variation of thermal

properties with the chemical composition of cement, properties of aggregate, mix proportion and

water cement ratio was also studied.

Keywords: thermal gradients, thermal conductance, degree of hydration.




46

SECM/13/48

ANALYSIS OF FOUR LEG TELECOMMUNICATION TOWERS FOR SEISMIC

LOADING USING RESPONSE SPECTRUM METHOD

A.M.L.N. Gunathilaka1 , C.S.Lewanagamage

2, M.T.R. Jayasinghe

3

1Sri Lanka Telecom PLC

Telephone:+94 -11-2451210; Fax:+94-11-2331426


2 University of Moratuwa

Telephone:+ 94-11-2650567; Fax: : + 94-11-2651216


3University of Moratuwa

Telephone: +94-11-2650567; Fax: + 94-11-2651216


Abstract

Telecommunication towers are common sight even in very remote areas of Sri Lanka with the revolutionary

development in this sector during last few decades. These towers play vital role especially in wireless

communication. Hence, a failure of such tower in a disaster like an earthquake is major concern since it

hampers communication needs in rescue operations during the disaster. Further, since these are usually tall

structures, failure of tower may itself cause a significant damage.

However, almost all existing telecommunication towers in this country have not been checked for seismic

loading since Sri Lanka was considered as a country free from earthquakes until recently. But, now most of

the structural engineers consider the seismic effects for their designs of important structure such as high rise

buildings, dams, etc. Still, this practice has not been implemented regarding telecommunication tower

designs.

This paper discuss the structural performance of selected existing four legged Greenfield towers which

were analyzed under seismic loadings using Response Spectrum method given in ANSI/TIA-222-G.

Approach of analysis and comparison of analytical results under different seismic analytical techniques as

well as with results under wind loading are presented in this paper.

Keywords: Telecommunication towers, seismic loading, Response Spectrum


47

SECM/13/49

OPTIMAL DESIGN OF A RETRACTABLE ROOF STRUCTURE USING REAL CODED

GENETIC ALGORITHM WITH HYBRID MUTATION OPERATOR

C. Mohanlal1, N. Murali Krishna

2

1 Department of Civil Engineering,

Vasavi College of Engineering , Hyderabad – 500031,India

Telephone number: +91 9989673220



University College of Engineering, Osmania University, Hyderabad-500007, India



Abstract

In this paper, discrete optimization of a retractable roof structural design using real coded genetic

algorithm with hybrid mutation operator is presented. Atypical retractable roof structure geometry

with few arch frames to support a set of stationary and movable planks is chosen here. To achieve the

opening or close position of roof, the movable planks slide on the supporting arches. The loads from

these movable planks get transferred directly on to the supporting arches at their respective joints. An

algorithm using C language is developed to generate entire geometry of the retractable roof structure

including the supporting arches. Design procedure incorporating real coded genetic algorithm with

hybrid mutation operator using discrete design variables is developed for optimizing the weight of

retractable roof structure. The objective function used here minimizes the weight subjected to the

constraints imposed by strength and serviceability requirements. A few benchmark problems that

demonstrate the suitability of the hybrid mutation operator are presented. Limit state method as per

IS: 800-2007 is adopted for steel design. The structural design of retractable roof is carried-out against

load combination due to dead loads, live loads and wind loads. While carrying-out analysis against

wind, the permeability of roof structure i.e. roof fully closed, partial open and full open conditions are

taken into consideration.

Keywords: Retractable roof, Genetic Algorithms, Optimization, Real coding, Mutation.



48

SECM/13/50

ASSESSING A WATER STORAGE SYSTEM IN THE ANURADHAPURA DISTRICT TO

IDENTIFY CLIMATE CHANGE MITIGATION MEASURES

Rodrigo B. S. A. H.1, Nayantha K. H. D.

2, Manamperi M. M. K. S. B.

3, Wijesekera N. T. S.

4

1University of Moratuwa












Abstract

Climate change has become a growing concern in the recent past where significant attention of

various intellectuals has been drawn to. The climate change is evident and various predictions

have been done in rise of temperature and changes in the rainfall. The predictions have been made

in terms of global scale as well as regional scale. Sri Lanka, being located close to the equator, is

expected to follow the regional predictions. Since the paddy cultivation in the dry zone based on

stored water, the impacts of climate changes are sever in the terms of small and medium size

reservoirs. These impacts to the reservoirs are critical in terms of economy and the food security

of the country. The majority of the paddy requirement is satisfied by the dry zone paddy and this

gives rise to study the sustainability of tanks under climate change scenarios. Though there are

general studies being done, no specific studies have been carried out to find out the differences in

behaviors of separate systems with actual data three reservoirs are selected from the dry zone of

Sri Lanka, namely Usgala Siyambalangamuwa, Nuwara Wewa and Tissa Wewa. Initially the

water balance model was developed using actual data and then a most representative data set was

obtained to represent each tank. Then the climate changes are incorporated into the representative

system by means of rise of temperature and reduction of rainfall. Reduction in the Yala Command

area by 10-50% was observed. Increasing the tank capacity is not a solution to cater climate

changes where the financial resources can be effectively used to increase the water management

system rather than increasing tank capacity. The differences of the behavior of three tanks

highlight the need of case studies in finding out impacts and mitigation measures under climate

change studies.

Keywords: Climate Change, Water Management, Anuradhapura District

49

SECM/13/51

DYNAMIC CHARACTERISTICS OF STIFFENED STEEL RIGID-FRAMES

Susantha, K.A.S.1, Kiriparan, B.

2, Nirusan, A.

2

1Department of Engineering Mathematics, Faculty of Engineering, University of Peradeniya,

Sri Lanka


2Department of Civil Engineering, Faculty of Engineering, University of Peradeniya, Sri Lanka.


.

Abstract

Displacement demand prediction is an essential and important component in performance based

structural design methodologies. Single pier substructures and rigid-frame pier bents are the most

commonly found structural form of elevated highways and overpass bridges structures in all over the

world. In this study, dynamic behaviour of rigid-frame substructure (i.e., single story stiffened

sectioned steel rigid-frame) subjected to different earthquake ground motions was studied. To this

end, nonlinear dynamic time history analyses incorporating geometrical and material nonlinearities

were conducted for a number of frames in order to check the displacement demand. A kind of fiber

analysis with the use of force-based beam-column element was carried out using research oriented

finite element program called OpenSees. The analyses were carried out for fifteen (15) ground motion

records to obtain the maximum displacement demand. The results showed that the predicted

maximum displacement demands exhibit linear relationship with respective acceleration responses of

frame structures. The effects of geometrical parameters on maximum displacement demand were

investigated in terms of column slenderness ratio p

moment of area ratio between beam and column (Ib/Ic). It was found that the maximum displacement

decreases with frame aspect ratio (h/L). It was also noted

change of maximum displacement with response acceleration decreases with Ib/Ic ratio. The effects of

Ib/Ic ratio seems to be diminished with increasing Ib/Ic ratio for the frames having comparatively

Keywords: Dynamic analysis, Finite element analysis, Seismic performance, Steel rigid- frames


50

SECM/13/52

DISPERSION OF POLLUTANTS IN AN ENCLOSED ROOM: A CASE STUDY ON AIR

FRESHENER

Perera T.M. 1, Jayasinghe C.

2, Perera S.A.S

3

1Department of Civil Engineering University of Moratuwa



2 Department of Civil Engineering University of Moratuwa



3Department of Chemical and Process Engineering University of Moratuwa

Telephone: +94 112 650301(Ext: 4122)


Abstract

Since the land is scarce in urban areas, more and more compact buildings are created for residential

and commercial purposes. Compact nature of buildings, demand mechanical ventilation systems, for

which air conditioners are the main source. This creates enclosed spaces inside the buildings causing

restricted fresh air supply. In order to remove the various accumulated odors, air fresheners are used

in most of the enclosed indoor spaces. Although air fresheners are provided pleasant odor inside the

room, it may contain some chemicals which would disturb the comfort level and health of the

occupants. The research presented in this paper was aimed at investigation of dispersion patterns of

pollutants due to spraying of air freshener in the enclosed spaces. A case study conducted in a test

chamber, includes the measurement of several pollutants such as TVOC, CO, CO2and PM2.5.

Dispersion patterns of the pollutants with time and distance was studied in detail. It was found that at

some distance points and up to a certain period of time, the concentrations of TVOC is much higher

than the threshold value. Also the toxicity index is more than one, which reveals that spraying of air

freshener can cause some discomfort to the occupants unless proper operational practices are adopted.

Keywords: Indoor Air Quality (IAQ), Air Freshener, Dispersion






51

SECM/13/53

DEVELOPMENT OF INTERLOCKING LIGHTWEIGHT CEMENT BLOCKS

R.Sayanthan1, S.Ilamaran

2, Mohamed Rifdy

3, S.M.A Nanayakkara

4


Telephone: +94-77-2935513



Telephone: +94-77-2262851



Telephone: +94-77-2266423



Telephone: +94-11-2650567-8(Ext.2113) Fax: +94-11-2651216


Abstract

Self-weight of building units, construction time and sound workmanship are key factors affecting the

quality and cost effectiveness of masonry construction. Amongst the loads a structure should resist,

self-weight is a major component thus the reduction of self-weight by introducing lightweight

material would effectively reduce the load as well as the cost of construction. Furthermore, large

individual units would help speedy construction and results in cost reduction. Yet, it is difficult to

achieve sound workmanship in construction of masonry works without skilled workers. By having

interlocking blocks, requirement of skilled workers can be reduced. Hence an experimental

investigation was carried out to develop interlocking lightweight cement blocks, contrary to those

existing, to address the above mentioned requirements. The interlocking hollow blocks developed are

600mm x200mm x200mm in size with a weight of 20 kg. The expanded polystyrene beads have been

used to reduce the self-weight. Experimental investigation has shown that average compressive

strength of block was 4.91N/mm2

and wall panel strength was 2.13 N/mm2, therefore it can be used

for load bearing masonry walls. It was also observed ductile load deformation behaviour at the failure

of the masonry wall panel, which is an added advantage.

Keywords: expanded polystyrene beads, interlocking blocks, lightweight.


52

SECM/13/54

DIRECT DISPLACEMENT LOSS ASSESSMENT OF EXISTING RC BUILDINGS

WITH AND WITHOUT SEISMIC ISOLATION: A CASE STUDY

D. Cardone1,A. Flora

2

1School of Engineering, University of Basilicata, Italy

Telephone: +390971205054; Fax: +391782254709


2School of Engineering, University of Basilicata, Italy

Telephone: +390971205054


Abstract

A case study of seismic retrofit of a high-rise RC frame building,using the seismic isolation

technique,is examined. The building under consideration is located in Potenza, southern Italy. The

building features 7 storeys in elevation plus 4 storeys partially underground, each with 30m by 12m

plan dimensions and approximately 3200 ton seismic mass. The building is adjacent to another

building, from which it is separated by a gap of 400mm. The isolation system used for the seismic

retrofit of the building is based on the combination of high-damping rubber bearings and flat steel-

PTFE sliding bearings. The isolation system has been inserted at the first storey above ground by

cutting the RC columns of the building.

In this paper,a performance evaluation of the building before and after the retrofit with seismic

isolation is carried out in terms of (direct and indirect) expected annual loss (EAL), applying a

simplified loss assessment methodology based on the principles of the Displacement-Based

Assessment (DBA) approachproposed by Priestley et al. (2007). The results of this study show a

considerable reduction of the EAL(greater than 50%), passing from the as-built to the retrofitted

configuration with seismic isolation.Finally, the time needed to get the break-even point between the

cost of the intervention and the benefits due to the EAL reduction has been calculated, resulting equal

to approximately 15 years.

Keywords: Seismic Retrofit, Seismic Isolation, RC frame buildings, Direct Displacement-based

Assessment, Expected Annual Loss.

53

SECM/13/56

DEVELOPING A FRAMEWORK TO BENCHMARK WATER EFFICIENCY IN

SUSTAINABLE COMMERCIAL BUILDINGS IN SRI LANKA

P.A.D. Rajini1,N. N.Jayaratne

2, S. R. Chandratilake

3


Telephone: +94 770640075; Fax: +94 112650738






Abstract

Buildings are considered as the places where significant amount of water is consumed and where

considerable savings can be captured. Therefore, water efficiency has become an important aspect of

a most of the green building rating tools that address the environmental performance of the entire

building. Benchmarking of water consumption figures has become a useful tool to motivate efficient

use of water in buildings. Further, it helps to find out how water efficient building is compared to

others in the same industry and to assess the possible measures for improvement. However so far, no

valid benchmark or a framework has been established to benchmark the water efficiency of

commercial buildings in the local context. Thus, the research aims at designing a framework to assess

the water efficiency in the context of Sri Lankan commercial buildings.

A quantitative research approach based on questionnaire survey was employed in order to attain the

objectives. The questionnaire survey identified the level of importance attached to each of the sub-

aspects of water efficiency by the expert from commercial property sector. Finally, this research study

presents the designing of an aggregate index that exemplify the degree of water efficiencythat a

commercial propertyachieved along the facet of sustainability.It provides a fine guidance for decision

making byconferring how the key performance indicators associated with water efficiency sub aspects

are normalized and finally aggregated into an overall index of water efficiency.

Keywords: Benchmarking, Green Buildings, Green Building Rating Systems, Water Efficiency,

Commercial Buildings






54

SECM/13/58

WASTEWATER TREATMENT, UTILIZATION AND MANAGEMENT IN SRI LANKAN

HEALTHCARE SECTOR: CASE OF STATE SECTOR HOSPITALS

M.J.N.M. Mithila1, K.G.A.S.Waidyasekara

2, P.A.D. Rajini

3

1 Department of Building Economics, University of Moratuwa, Sri Lanka

Telephone: +94 772 314 693






Abstract

Hospitals are highly populated facilities which functions 24 hours a day. They generate large amount

of wastewater through various sources which are very complex and hazardous. Furthermore, the

emission of healthcare wastewater into the cities sewerage, rivers and groundwater pollute the entire

system. Therefore, disposal of healthcare wastewater without adequate treatment can cause short and

long term ill effects to public‟s health. An onsite wastewater treatment would give a duel benefit of

preventing the release of hazardous materials into other sources and bring the wastewater into the

consumption cycle. At present, most of the countries utilize the treated wastewater in order to reduce

the consumption of potable water. However, the literature review and preliminary studies revealed

that wastewater management ispoorly practiced in Sri Lankan healthcare sector. Therefore, this paper

aimed to identify the extent of wastewater treatment, utilization and management in Sri Lankan state

sector hospitals.

The aim of the paper was achieved through literature review and questionnaire survey.The required

data was collected from nine state hospitals in Colombo. Findings of the study revealed that a high

quality of wastewater treatment and efficient reuse of reclaimed water is a big challenge for the

healthcare sector due to the complex nature of wastewater process, higher cost of treatment and poor

management. Moreover, it was found that currently wastewater generated from the state hospitals are

discharged directly in to the cities sewerage without any treatment. Finally this paper discusses the

current level of wastewater treatment, utilization and management in the state hospitals and identifies

the critical barriers for the lack of poor practice of wastewater handling.

Keywords: Healthcare Sector, Reclaimed Water, Wastewater, Wastewater Management






55

SECM/13/59

EFFECT OF ALBEDO ON SURFACE TEMPERATURE OF CONCRETE INTERLOCKING

PAVING BLOCKS IN MITIGATING URBAN HEAT ISLANDS

A.S. Asmone1, S.R.M.S.R. Chandrathilake

2, R.U. Halwatura

3

1Department of Building Economics, University of Moratuwa, Sri Lanka.

Telephone: +94 776 221785



Telephone: +94 770 861446


3Department of Civil Engineering, University of Moratuwa, SriLanka.

Telephone: +94 777 704826


Abstract

Out of the environmental impacts of anthropogenic activities and urbanization, urban heat island effect

(UHIE) is considered most prominent and is identified to have many socio-economic implications, such as;

deterioration of living environment, increased energy demand, elevation of ground level ozone and smog

events, adverse health conditions and even increase in mortality rates. The progressive replacement of

natural environment is identified as a major cause of UHIE.

Pavements are identified as a countermeasure to reduce urban heat, whereas this paper evaluates how

existing pavements can be modified using surface treatments and how much a reduction of urban heat can

be expected from that using surface energy balance model. Experimental measurements were taken of

different coloured (albedo) pavers, and how it affects the surface temperature of the installations.

It was identified that lighter coloured surfaces are cooler than conventional dark pavements; hence albedo

can be used in countering the effects of UHI. However, considerations have to be made about the decrease

in surface albedo with traffic and weathering of pavers. This study was limited to surface thermal properties

of concrete interlocking pavement blocks in tropical climate conditions, which can be used in green building

design and construction projects in Sri Lanka.

Keywords: Urban heat islands, Concrete interlocking pavement blocks, Albedo, Surface energy balance

56

SECM/13/60

USE OF WATER TOWARDS ENVIRONMENTALLY SUSTAINABLE CONSTRUCTION:

RULES, REGULATIONS AND TRADITIONS

K.G.A.S. Waidyasekara1,M.L De Silva

2, R.Rameezdeen

3


Telephone: 0773640989; Fax: 0112650738




3University of South Australia, Adelaide, Australia


Abstract

Water serves multiple purposes and it is an important input for economic development and social

development of a country. The distribution of water throughout the earth is not uniform. In the present

context, water is becoming an increasingly scarce resource with population growth and climate

change. Therefore, it is being an outstanding global issue and many countries are struggling with

demand and supply of water imbalances. Many researches have predicted that there can be a water

shortage by the year 2025 including Sri Lanka and entire world will be in danger if not implemented

proper conservation plans. While moving towards sustainable approach in many industries, water is

one of the important natural resources consumed by the construction industry which uses water in

almost all the activities. However, use of potable water, inefficient and wasteful misuse of water could

be seen at all the time in many construction projects. However, it‟s wise used is a prerequisite for

sustainable development.

Therefore, this paper provides the clear picture on the existing rules, regulations and environmental

policies that addressed towards the efficiency and conservation of water used in construction projects.

In the research process, initially a comprehensive literature synthesis and documentary review were

carried out. This was then followed by interviews among the professionals who represent the relevant

authorities and contractor organizations in Sri Lanka. Moreover, the paper elaborates the existing

tradition and how water use for construction projects minimizing environmental impacts towards

sustainable construction.

Keywords: Construction projects; regulations; sustainable construction; water use





57

SECM/13/61

STRUCTURAL ISSUES OF PIPELINES AT EARTHQUAKE FAULTS

1Rupa Purasinghe,

2H.Lum ,

3J. Shamma,

4X. Zheng,

5L. Dam

1California State University at Los Angeles,Los Angeles, CA 90032

Telephone:323-343-4459


2,3,4,5

California State University at Los Angeles,Los Angeles, CA 90032

Abstract

For underground structures and lifelines in seismically active zones, structural performance can be

determined by assessing the anticipated ground strains and fault ruptures. In particular, lifelines

crossing active faults are vulnerable to breakage as large displacement induces rupture at fault

locations. The probability, magnitude and direction of fault rupture during a major earthquake event

are of primary concern, since this could result in pipeline damage or failure. In order to mitigate

pipeline damage, water utilities in United States and elsewhere have introduced designs that will

allow pipelines to deform with the ground while maintaining the structural integrity for continuous

service after an earthquake.

This research evaluates pipeline behavior subject to fault displacement by simplified testing of steel

pipelines in a lab environment that simulates a fault rupture. An approach using an enlarged

excavated section at fault crossing with cellular concrete backfill was used to allow the pipeline to

accommodate the large fault displacement. The laboratory tests provide stress-strain deformation data

for both the cellular concrete encased pipe and plain steel pipe subject to progressive loading until

failure. Data obtained through these tests will explore the correlation between field installed pipelines

and laboratory test cases. This research will allow engineers to develop predictive tools for pipeline

behavior at fault crossings and better design the lifelines in response to large ground deformations.

Keywords: Seismic safety of lifelines, fault rupture, pipeline safety, structural simulation


58

SECM/13/62

EFFECT OF THE ACTIVITIES INSIDE A HOSPITAL THEATRE ON ITS IAQ

Gunaratne W. D. S. P.1, Gunatilake M. M. D. V.

2, Jayasinghe C.3, Madushanka H. K. R.

4, Perera

T.M.5, Perera S.A.S.

6, Rajapaksa S.

7


Telephone: +94(71)6510735 ; Fax: +94(11)2651216



Telephone: +94(77)6049090 ; Fax: +94(11)2651216



Telephone: +94(77)7310890 ; Fax: +94(11)2651216



Telephone: +94(71)5376981 ; Fax: +94(11)2651216



Telephone: +94(77)2514814 ; Fax: +94(11)2651216


6Department of Chemical and Process Engineering, University of Moratuwa, Sri Lanka.

Telephone: +94(77)7717895 ; Fax: +94(11)2650622


7National Cancer Institute of Sri Lanka

Telephone: +94(77)3409787


Abstract

A close relationship can be observed between the building performance and the activities associated

with the building. Since those activities have a great impact on Indoor Air Quality (IAQ) of the

building, it is necessary to consider the activities that would take place inside a building, at its design

stage.In this research study, the effect of the activities associated with a hospital theatre, on its IAQ

has been studied since the theatre staff of a leading hospital in Sri Lanka, experience some discomfort

while being inside the theatre. In order to evaluate this, variation of Carbon Dioxide (CO2), Carbon

Monoxide (CO), Total Volatile Organic Compounds (TVOC) and Particulate Matter less than 2.5

microns (PM2.5) concentrations inside the theatre were measured and analysed.

Significant variations were observed in the concentrations of CO2, TVOC and CO inside the operation

theatre. CO2 concentration inside the room increased at the beginning and end of the surgeries due to

high occupant density and also during Laparoscopic surgeries. TVOC concentration was affected by

the usage of different chemicals during the surgery. Major effect to the CO concentration was by

Diathermy

Keywords: Indoor Air Quality (IAQ), Hospital theatre, Sick Building Syndrome (SBS)















59

SECM/13/63

DESIGNING AND IMPLEMENTING SUSTAINABLE ONSITE WASTEWATER

TREATMENT SYSTEMS

R. Purasinghe1, H. Mmeje

2, B. Bradley

3, T. Ezeh

4, S. Mamun

5

1Department of Civil Engineering, California State University, Los Angeles.

City of Los Angeles, Bureau of Sanitation, Wastewater Engineering Services Division.

Telephone: (323) 342-1561


2City of Los Angeles, Bureau of Sanitation, Wastewater Engineering Services Division.

Telephone: (323) 342-6241


3Advanced Onsite Systems, Inc.

Telephone: (760) 743-8777


4City of Los Angeles, Bureau of Sanitation, Wastewater Engineering Services Division.

Telephone: (323) 342-1590


5Department of Environmental Engineering, California State University, Los Angeles

Telephone: (323) 342-6024


Abstract

Onsite Wastewater Treatment Systems (OWTS, also known as septic systems) are used throughout the

world for domestic, industrial and commercial wastewater treatment where sewer is unavailable. Property

owners are highly dependent on OWTS to properly function as they serve a vital role for safe wastewater

disposal and protecting public health and the environment. With aging infrastructure and higher water

quality standards, it is important that the full cycle engineering project design and implementation process

be clearly understood by all parties involved. This paper goes into detail about the 5 key steps involved in

the engineering design and implementation process of OWTS, including: (1) Planning for flow capacity,

water quality, feasibility and reviewing current infrastructure; (2) Pre-Design for percolation rates, slopes,

environmental and health impacts and other site conditions; (3) Full Design for developing specifications

and selecting the correct dispersal system for the site conditions; (4) Construction, permitting, inspection,

and project acceptance; (5) project implementation and development of operation and maintenance

procedures. All 5 steps of the engineering process are detailed in the paper and are to be followed by

building inspectors, construction engineers, geotechnical engineers/geologists, registered environmental

health specialist and environmental engineers.

Keywords: Wastewater Treatment Systems, flow capacity, water quality, percolation rates, health impacts





60

SECM/13/64

CONSTRUCTION SITE SAFETY IN SRI LANKA

1Ahamed Rafa I.T,

2Asjathu U.M,

3Halideen I.,

4P.B.G. Dissanayake

1,2,3 Department of Civil Engineering , Faculty of Engineering,University of Peradeniya

Email:[email protected],

[email protected],

[email protected]

4Department of Civil Engineering, Faculty of Engineering,University of Peradeniya


Abstract

The main objective of this study is to identifying the issues related to building construction site safety

and to propose measures to improve the site safety of Sri Lankan building construction industry.

Through this study it is intended to find the likely causes that may lead to accidents and their effects.

The negligence on safety aspects lead to loss of productivity, accidents and poor health issues.

Therefore, this study will investigate safety planning & precautions, regulations and the adoption of

safe construction methods in the building construction and also focus on awareness of personnel to the

ordinances related to construction safety in Sri Lanka.

The research was carried out through questionnaire surveys and personal interviews with industry

professionals and policy making bodies. The preliminary data for this research were collected through

a literature survey. The causes and impacts of accidents were grouped under job factors, human

factors, managerial factors and acts of nature in a structured questionnaire based on the literature

survey and the opinion of the industry experts. The relative importance index method will be used to

rank the factors based on the perceived importance of the respondents.

It is expected that this study will help identify the most the significant causes of accidents and come

up with suggestions to improve the site safety of the Sri Lankan construction industry.

Keywords: Sri Lankan Construction Industry, Site Safety, Accidents, Relative Importance Index


61

SECM/13/65

CHALLENGES FACED BY CONTRACTORS IN THE CONSTRUCTION INDUSTRY OF

SRI LANKA

1Arachchi L.A.T.L,

2Jayasooriya H.M.K.K.B,

3 Kumara M.R.,

4 P.B.G. Dissanayake

1,2,3,4

Department of Civil Engineering, Faculty of Engineering, University of Peradeniya

Email: [email protected] ,

4 [email protected]

Abstract

The objective of this study is to identify challenges faced by contractors in the construction industry

of the Sri Lanka and suggest mitigation measures to minimize the effects. This study can be

considered very timely and important in the present context of the Sri Lankan construction industry.

This study was done out through questionnaire surveys carried out among contractors, consultants and

construction industry professionals (administrators, professionals, technicians, supervisors, and

similar grades). The survey was carried out in two stages with a preliminary survey followed by a

detailed survey. The preliminary survey was conducted in order to get the ideas and opinions of the

construction industry professionals and technical personnel via interviews. The questionnaire for the

detailed survey was prepared based on the findings of the preliminary survey. Based on the literature

review, ten major areas were identified namely, financial, government and policies, construction

knowledge, discrepancies between client and contractor, management and coordination, resources,

safety, social factors, skills of employees and completion of contact. This study is mainly focusing on

the above areas in detail. Random sampling was used to select a representative sample from the

population. Analyzing method used in this study will be based on the Relative Importance Index (RII)

which can be derived from the Severity Index (SI) and Frequency Index (FI). The RII will be used to

find the most important challenges faced by the contractors by ranking the identified challenges in

ascending order.

It is expected that this study will be able to identify the most significant challenges faced by the

contractors in the construction industry of the Sri Lanka and how the effects could be mitigated.

Keywords: Construction Industry, Challenges, Questionnaire Survey, Relative Importance Index,

Severity Index, Frequency Index


62

SECM/13/66

BOND PERFORMANCE OF CFRP STRENGTHENED STEEL MEMBERS SUBJECTED TO

AXIAL COMPRESSION

S. Abeygunasekera1, J. C. P. H. Gamage

2, S.Fawzia

3


Telephone: +94777175042



Telephone: +94112650567-8 (Ext 2201); Fax: +94112651216


3School of Civil Engineering and Built Environment, Faculty of Science and Engineering, Queensland

University of Technology, Australia

Telephone: +61 7 3138 1012


Abstract

This paper focuses on the use of externally bonded Carbon Fiber Reinforced Polymer (CFRP)

materials to strengthen steel plates subjected to compression. A fully slender steel section was

selected in this test programme. CFRP strengthened steel plates and non strengthened plates were

tested to fail under compressive load. The middle part of the strut was strengthened using CFRP sheet.

The length of the strengthened zone was varied. Eight specimens were tested in this test programme.

The test results showed a significant strength gain of 47% and delaying of lateral torsional buckling

failure mode of strengthened members. This study confirms that there is great potential to increase the

short term performance of CFRP strengthened steel structure under axial compression.

Keywords: CFRP/steel composites, Bond length, Bond performance, Axial Compression





63

SECM/13/67

CFRP-CONCRETE BOND BEHAVIOUR: EPOXY VS CEMENT BASED ADHESIVES

P.G.Nishanthan1, J. C. P. H. Gamage

2

1School of Technology,University of Wolverhampton, United Kingdom,

Through CINEC Maritime Campus, Sri Lanka

Telephone: +94652222592; Mobile: +94716067637





Abstract

There is a constant need for repair or strengthening of existing concrete structures due to higher loads,

degradation or damages caused by disaster. Different strengthening techniques and materials are

available for retrofitting concrete structures. One relatively new technique for strengthening is the use

of externally bonded Carbon Fiber Reinforced Polymers (CFRP) sheets or plates. This technique is

very efficient and has achieved worldwide attention. However, the epoxy adhesive used in Civil

Engineering constructions is very sensitive to the elevated temperature and moisture. Substituting the

epoxy adherent with a cement based bonding agent will render a strengthening system with improved

performance, better compatibility to the concrete substrate with minimum health hazards in the

installation phase. This paper presents a review of bonding techniques, limitations of using epoxy

adhesive and performance of cement grout as a bonding agent.

Keywords: CFRP/concrete, Epoxy, Polymer mesh, Debonding failure



64

SECM/13/68

BEHAVIOUR OF PARTIALLY SLENDER STEEL COMPOSITE COLUMNS

M. Rajeevan1, J. C. P. H. Gamage

2

1 Department of Civil Engineering, University of Wolverhampton, United Kingdom, Through CINEC

Maritime Campus, Sri Lanka

Telephone: +94775384626





Abstract

This research aims to investigate the effects of fill height and fill materials of thin shell hollow axially

loaded compression members on buckling behaviour. A total of eighteen specimens were tested.

Locally available clay and grade 10 concrete were selected as fill materials. The results show the

buckling load of thin shell composite compression members are dominantly affected by the

geometrical imperfections present in the cylindrical shell which are very difficult to alleviate during

testing process. This paper presents the detail of test programme, results and recommendations.

Keywords: Thin shell, composites, compression


65

SECM/13/69

EFFECTS OF FILL MATERIALS ON PERFORMANCE OF COMPOSITE COMPRESSION

MEMBERS

M.R. Rizadh Ahamed1, J. C. P. H. Gamage

2

1Department of Civil Engineering, University of Wolverhampton, United Kingdom, Through CINEC

Maritime Campus, Sri Lanka

Telephone: +94776003032





Abstract

This paper presents an experimental study on the behavior of composite stainless steel columns

concentrically loaded in compression to failure. Twelve specimens were tested. Partially slender

column sections were selected for this study. Three types of filing materials; concrete, cement

stabilized soil and porous concrete were used. Effects of fill height on composite performance were

also investigated. Experimental results suggest that concrete filled circular tubes offer substantial

post-yield strength and stiffness, not available in porous concrete or cement stabilized soil as filling

materials. The variation of strength of composites, failure mechanisms and performance of different

filling materials are also discussed in this paper.

Keywords: Thin shell, composites, compression, fills height, filling materials




66

SECM/13/70

COMPARISON OF STRENGTHENING TECHNIQUES FOR REINFORCED CONCRETE

BEAMS

N.A. Razmy1, J. C. P. H. Gamage

2

1School of Technology, University of Wolverhampton, United Kingdom, Through CINEC Maritime

Campus, Sri Lanka

Telephone: +94759117200





Abstract

Civil Engineering infrastructures deteriorate rapidly due to many reasons such as environmental

exposure, fatigue and increased loading. Strengthening of infrastructures is important to the country‟s

economy, especially for developing countries. Engineers have been used different materials and

strengthening techniques to retrofit existing structures. However, the selection of a good alternative

will save the time and cost of the strengthening project.

Use of traditional materials and methods for strengthening is popular in Sri Lanka. However,

retrofitting of structures using Fiber Reinforced Polymer (FRP) materials provides many advantages.

This paper reveals the most utilized techniques for strengthening of reinforced concrete beams, with

their advantages and disadvantages. Preliminary testing was carried out to ensure performance of

Carbon Fiber Reinforced Polymer (CFRP) strengthening technique for tropical climate. This paper

will also provide the overview of test programme and performance in flexure and shear.

Keywords: Strengthening techniques,CFRP/concrete composites, Flexure, Shear


67

SECM/13/71

HYDRAULIC PERFORMANCE OF GABIONS IN COASTAL STRUCTURES

R.S.M. Samarasekara1, S.S.L. Hettiarachchi

2, S.S. Priyankara

3, H.A.M. Silva

4


Telephone: +94-718212277



Telephone: +94-11-2650567-8(Ext.2114); Fax: + 94-11-2651216



Telephone: +94-714973349



Telephone: +94-718406677


Abstract

Gabion structures are utilized for the protection of river and estuary banks and coast and as temporary

structures for loading in fishery harbours. These structures, though temporary have performed well for more

than a decade in coastal engineering practice in Sri Lanka. They have withstood the coastal environment,

including near-shore waves, estuarial waves, waves within harbours and wave arising from vessels. The

study has reviewed the performance of different types of gabion structures. This paper has identifies wave

structure interaction in relation to wave energy dissipation characteristics. The relevance of selecting the

appropriate type of structural configuration to overcome undesirable impacts of wave reflection is

highlighted. Attention is focused on to have maximum energy dissipation characteristics while reducing the

influence of wave reflection. The performance of the structures is discussed in the context of importance of

porosity and permeability of wave absorbing structures. The investigations have also provided important

observations on the response of the design parameters. Gabion structures provide the wave energy

dissipation across the structure as a basis for improved design by economizing on the geometry. The

investigations have further provided important observations on the response of the design parameters to

varying incident wave conditions. The collection of experimental results from such large scale

investigations will enhance the knowledge base of the subject and will strengthen the existing computational

methods leading to more economical design.

Keywords: Energy Dissipation, Gabions, Hydraulic Performance, Wave


68

SECM/13/72

SUSTAINABILITY IN POST DISASTER ROAD INFRASTRUCTURE RECOVERY

PROJECTS AND ASSET MANAGEMENT

1Ruwan Weerakoon,

2Arun Kumar

1Rockhampton Regional Council,1 Broadhurst Drive Gracemere 4702,Queensland, Australia

Telephone:+61427633120

Email: [email protected] ;[email protected]

2Queensland University of Technology,GPO Box 2434 Brisbane,Queensland, Australi

Telephone:+6173138 2731; +61411040481

Email: [email protected];[email protected]

Abstract

Civil infrastructure and especially roads are being impacted with increasing frequency by flood,

Tsunami, cyclone related natural and manmade disasters in the world. Responding to such events and

in preparing for more regular and intense climate-change induced events in future, the road governing

agencies are reviewing how post-disaster road infrastructure recovery projects are best planned and

delivered. In particular, there is awareness that rebuilding such infrastructure require sustainable asset

management strategies across economic, environmental and social dimensions.

A comprehensive asset management framework for pre and post disaster situations can minimize

negative impacts on our communities, economy and environment. This research paper is focused on

post disaster management in road infrastructures and road infrastructure asset management strategies

used by road authorities. Analyzing the implications of disruption to transport network and associated

services is an important part of preparing local and regional responses to the impacts of disasters. This

research paper will contribute to strategic infrastructure asset planning, management leading to safe,

efficient and integrated transport system that supports sustainable economic, social and environmental

outcomes.

This paper also focuses on proper asset management, governance and engineering principles which

should be followed and adopted in post disaster recovery projects to maximize sustainability in

environmental, social and economic dimensions.

Keywords: Sustainability Assessment Framework, Asset Management, Post Disaster Road Recovery

Projects.





69

SECM/13/73

INVESTIGATION ON EFFECTIVE USE OF CFRP LAMINATES FOR FLEXURAL

PERFORMANCE

D.M.N. Wijerathne1, J. C. P. H. Gamage

2


Telephone: +94711867502





Abstract

Use of Fibre Reinforced Polymer (FRP) materials for strengthening concrete structures is widely

gaining appeal worldwide due to its superior properties such as light weight, high strength and

stiffness, resistance to corrosion and flexibility. Among those materials, Carbon Fibre Reinforced

Polymer (CFRP) has extensive properties over other fiber types; negligible affect by water and high

resistance to Ultra Violet radiations. Therefore it is very beneficial to use CFRP for retrofitting

infrastructures. Strengthening for shear with CFRP has been researched extensively and design

guidelines are also available. However it is also possible to enhance shear capacity of beams using

pre-stressed CFRP sheets. Higher tensile strength and higher Young‟s modulus of CFRP supports this

concept very much. The behavior of eight pre stressed CFRP strengthened beams were tested using

four point bending test. The results show a significance strength increment with pre-stressed level.

This paper presents the preliminary test programme, results and recommendations.

Keywords: CFRP/concrete, Epoxy, pre stressed CFRP, Shear


70

SECM/13/74

EFFECTS OF SURFACE ROUGHNESS ON FLEXURAL PERFORMANCE OF

CFRP/CONCRETE COMPOSITES

M.R.E.F. Ariyachandra1, J. C. P. H. Gamage

2


Telephone: +94719085399





Abstract

Carbon Fibre Reinforced Polymer (CFRP) composites have been progressively more utilized to

strengthen the concrete members to improve its flexural performance. Flexural capacity of CFRP

strengthened concrete members mainly hinge on controlling probable failure modes. The interfacial

bond failure takes place owing poor surface preparation for FRP application which grounds a bond

failure between concrete and adhesive eventually. Preparation of concrete substrate plays a significant

role in terms of engendering strong bond between FRP - concrete interface. Achieving uniform

surface roughness all through the concrete substrates is the major issue in surface preparation

procedure since the uniformity of the roughened concrete substrates totally depends on the human

skills and experience. Existing surface roughness quantification methods have a substantial

discrepancy although a unique quantification method is essential more imperatively. In the present

study, experimental investigation was focused on the flexural performance of the externally

strengthened CFRP concrete beams with different types of surface preparation levels. The surface

roughness of the concrete substrates was determined by means of a standard quantification method.

Concrete beams were subjected to three point bending test and failure modes were observed. The test

results point out a significant effect on the flexural capacity of CFRP strengthened concrete beams

with the surface roughness levels.

Keywords: CFRP, flexural performance, failure modes, surface roughness, surface preparation


71

SECM/13/75

ALTERNATIVE BONDING TECHNIQUES TO DELAY END DEBONDING OF CFRP

STRENGTHENED REINFORCED CONCRETE BEAMS

H.R.D. Premarathne1, J.C.P.H. Gamage

2


Telephone: +94718454964





Abstract

The use of Carbon Fibre Reinforced Polymer (CFRP) as external reinforcement for concrete

structures is growing rapidly. This is due to many advantages offered by these materials compared to

conventional steel reinforcements such as high strength to weight ratio, good fatigue properties, non-

corroding characteristics, high degree of chemical inertness, controllable thermal expansion, damping

characteristics and simplicity of application. Rehabilitation and strengthening of existing concrete

structures can be done up to a significant level with correctly applied CFRP sheets. However CFRP

strengthening systems subject to end de-bonding failure before reaching its full capacity. This study

was focused on investigation of alternative bonding techniques to enhance strength gain by delaying

premature failure of composite laminate. A total of six specimens were tested to determine the

flexural capacity using three point bending test. The specimens were prepared with three different

CFRP sheet arrangements. This paper presents the test program, results and conclusions.

Keywords: CFRP/ Concrete, Flexure, De-bonding, bond enhancement


72

SECM/13/76

APPLYING THE KIRCHHOFER SYNOPTIC TYPING FOR COMPARISON OF

PREDICTED COASTAL SYSTEMS AND MEASURED DATA

Pushpa Dissanayake1,RoshankaRanasinghe

2

1College of Engineering, Talbot Building, Swansea University, UK.

Telephone: +44 1792 295540; Fax: +44 1792 295676


2Department of Civil Engineering, Delft University of Technology, Delft, the Netherlands.

Telephone: +31 15 215 1805; Fax: +31 15 212 2921


Abstract

Numerical models are increasingly adopted to hindcast/forecast the evolution of coastal systems. Reliability

of these approaches depends on the similarity of predicted morphology with data, which are used to

compare applying statistical parameters (e.g. R2) or Brier Skill Score (BSS). These techniques have proven

deficiencies to cope with some individual characteristics of a system. Therefore, it is a long time need to

have an accurate tool to determine the model skill. Paper presented herein describes Kirchhofer Synoptic

Typing (KST) which has originally been developed to classify the weatherpatterns.

Evolution of two hypothetical coastal systems, 1) sand-hump, 2) cross-shore channel and a schematised

tidal inlet/basin system which is analogous to the Ameland inlet in the Dutch Wadden Sea (the Netherlands)

were applied to estimate the performance of KST over the R2 and BSS classifications. Sensitivity of each

parameter was investigated in terms of amplitude and phase changes. In all test cases, KST showed a strong

sensitivity with respect to the phase change while it is negligible to the amplitude change. Similar trend was

found with the R2 and BSS also. In contrast to the latter two parameters, KST indicates the changes in

columnwise and rowwiseof the domain which is very useful to find the similarity of the predicted

morphological evolution with data.More test cases and analyses are required to draw anultimate conclusion

of potential application of KST in coastal systems.

Keywords: Kichhofer Synoptic Typing, numerical model, coastal systems, model comparison



73

SECM/13/77

EFFECTIVENESS OF SOFTWARE APPLICATION IN CONSTRUCTION PROJECT

MANAGMENT

1Gayan Manorathna,

2Rangika Halwatura

1United Nations Office for Project Services




Telephone: 0777-704846


Abstract

Today, construction industry is becoming complex due to rapid improvement with design &

technology. Completing project without time and cost overrun is a great challenge. In Sri Lankan

condition, the need for efficient management is more urgent than ever before. Professional

construction project management input is a mandatory requirement for successful project completion

and one tool which can used to manage a project is project management software. The focus of this

research was to gather industry experience in application of construction management software and to

assess the difficulties & benefits realised by the industry.

The study was conducted under three main areas in management and was done through a

questionnaire based interview. Data collected were used to understand the position where construction

firms stands in terms of software usage for project management activities in Sri Lankan construction

industry.

Over 80% of firms are using MS Project as project management software & usage was limited only

for initial basic facilities provided by software and very less usage in cost & resource related

activities.

Providing easy administration of works, integration & approach to repetitive tasks, Force due to competitors

& consultants are most important factors highlighted as reasons for usage.

Non availability of trained staff & Lack of interest among top management are significant difficulties faced.

Only 35% of firms have a plan to develop their software systems.

Keywords: Effectiveness of Software Application in Construction Project Management

74

SECM/13/78

EFFECT OF INDUCED VIBRATION ON FRESH CONCRETE

R. Islam1, S. Ferdousi

2 and M. Akhtar

3

1Department of Civil Engineering, Khulna University of Engineering &Technology, Bangladesh

Telephone: +8801680380543



Telephone: +8801918293174



Telephone: +8801676110358


Abstract

Concrete is an artificial kind of stone prepared from an indefinite mixture of three basic components

such as binding materials, inert materials and water. When the components are mixed together to

prepare concrete, binding materials such as cement paste acts as a glue binding surrounding the inert

materials during the process of hydration and curing. The freshly mixed concrete becomes hard with

considerable strength following the setting procedure of cement. During the setting period, vibration

may come on fresh concrete as a result of earthquake, pile driving, heavy traffic or vibratory soil

compactors. The objective of this research was to perform a laboratory test to find out the effect of

vibration on working strength of concrete between the initial and final setting period. On this purpose,

two different sizes concrete cylinders (4”X8” and 6”X12”) were casted by mixing cement, sand, stone

chips and water with two ratios (1:2:4 and 1:1.5:3). Water-cement ratio was 0.78. The initial and final

setting time were recorded as 140min and 270 min respectively. The concrete cylinders were then

subjected to two level of vibration for 1 min or 2 min at three different ages (2 hr, 3.5 hr and 5 hr) by

the help of shaking table. The peak particle velocities were 50mm/s -100mm/s, 150mm/s and

200mm/s-300mm/s. About 96 cylinders were tested for compression and splitting tensile strength tests

at 7 days and 28 days. From the test results it was found that, the compressive strength was increased

up to 20% and the tensile strength was decreased up to 13% over the controlled cylinder specimen by

the effect of vibration.

Keywords: Fresh Concrete, Setting time, Vibration, Compressive Strength, Tensile Strength.



75

SECM/13/79

NUMERICAL SIMULATIONS ON EPOXY BOND PERFORMANCE OF CFRP/CONCRETE

COMPOSITES ENHANCED WITH POLYMER MESH

S. Srisangeerthanan1, J. C. P. H. Gamage

2


Telephone: +94777102481





Abstract

Fibre reinforced polymers, with the use of an epoxy binder, have emerged as the most commonly used

strengthening material for structures that have deteriorated due to aggressive environments. They are widely

sought due to their exceptional material, mechanical, chemical and time dependent properties inclusive of

their durability and constructability related aspects. Though CFRP possesses such qualities, the interfacial

bond between CFRP and the concrete substrate is highly susceptible to premature failure. However, the

most prevalent form has been found to be of a debonding nature. Hence much research has been done

related to its understanding and many more for achieving its delay or prevention.

Among the techniques proposed for bond enhancement to delay premature failure due to debonding, the use

of a polyester mesh as a bond reinforcing medium had shown promising results. The FE model developed

to identify the flexural performance with modified bond line is well agreed with experimental results. This

paper presents the behavior of CFRP strengthened beam with improved bond line and also behavior of the

interface and polymer mesh.

Keywords: CFRP/concrete, Epoxy, Polymer mesh, Debonding failure


76

SECM/13/80

EFFECT OF EXTERNAL FACTORS, WITHIN A GREEN BUILDING - A CASE STUDY

A.W.L.H. Ranasinghe1,R.U.Halwatura

2


Telephone: +94 771 970200



Telephone: +94 777 704826


Abstract

The concept of “Green Building” became the most prominent among new building designs, which

was set up with the “Sustainable Built Environment”, to safeguard the natural environment. With

boom of this new concept of sustainability, necessity was arisen to find out whether the occupants of

these green buildings are physically and mentally satisfied within their habitat. The study was carried

out in two phases within a LEED platinum rated building and from the phase I, it was found that the

selected workplace has located within the extended comfort zone, but physically the occupants were

not thermally comfortable and that lead to their dissatisfaction with respect to the comfort. During

Phase II, further analysis was carried out concerning, internal level of CO2 and radiation and so as to

a conclusion that, due to insufficient consideration on some important design aspects which were not

covered in the LEED guidelines, which was established by USGBC, physically and mentally the

building was not thermally comfortable for the occupants. Therefore, this research emphasized while

ensuring the great standards within the green buildings, the designers need to be daring enough to

look beyond the standards to make the occupants satisfied within their workplace.

Keywords: Sustainable Built Environment, Green Buildings, LEED, Occupant’s satisfaction,

Thermal Comfort.




77

SECM/13/83

SETTING AND STRENGTH CHARACTERISTICS OF FaL-G PASTE

P S Niranjan1 , Radhakrishna

2


Telephone:+919845788345




Abstract

FaL-G is the product name given to a cementitious mixture consisting Fly ash (Fa), Lime (L) and

Gypsum (G) in a definite proportion. It is a low-cost and environmental-friendly material very useful

especially in case of rural housing industry. Since it is manufactured using industrial wastes and by-

products, the environmental impacts are mitigated. This paper addresses the technology of making

compressed FaL-G cementitious paste with low-calcium (Class F) dry fly ash procured from different

sources. The cardinal aim is to study the setting and strength characteristics of FaL-G paste. Its

applicability as controlled low strength material is also ascertained. The FaL-G paste cylinders were

prepared without the use of conventional cement. The compressive strength of FaL-G paste cylinders

were tested for different proportions. It was noticed that the strength of FaL-G paste increases with

age and adequate to use it in making deferent composites. FaL-G paste can also be used as controlled

low strength material, as it has good relative flow area and adequate strength development.

Keywords: FaL-G, fly ash, lime, Gypsum, paste, compressive strength.



78

SECM/13/84

A DESIGN CRITERION TO PREDICT SHORELINE RESPONSE TO SUBMERGED

BREAKWATERS

R. Ranasinghe1, M. Larson

2, J.Savioli

3, A. Luijendijk

4, N. Blouin

5

1,2

Department of Water Engineering, UNESCO-IHE/Delft Univ. of Technology/Deltares,

Netherlands.

Telephone: +31 646843096; Fax: +31 152122921


2Department of Water resources Engineering, Lund University, Sweden


3DHI Water and Environment, Selangor, Malaysia.


4Harbour, Coastal and Offshore Engineering, Deltares/Delft Univ. of Technology, Netherlands


5Coastal Engineering, Genivar inc.,Quebec, Canada.


Abstract

Submerged breakwaters (SBWs) are now becoming a popular option for coastal protection due to

their low aesthetic impact. However, a robust design criterion to predict the mode (i.e. erosion or

accretion) and magnitude of shoreline erosion/accretion in response to SBWs has not been developed

to date. This study describes the development of such a design criterion using numerical modelling

techniques.

The structural and environmental variables that may govern shoreline response to a SBW are:

structure length (LB), structure width (wB), depth to crest of structure (sB), depth to sea bed at structure

(hB), distance to structure from shoreline (xB), wave height (Hs), wave period (T), wave direction ( ),

tidal range (R). The formation of a salient in the lee of a SBW depends on the ratio () between the

onshore flow over the SBW (QC) and the alongshore flow due to alongshore setup gradients and/or

oblique wave incidence (QL). Following a few simplifying assumptions, it can be shown from

dimensional analysis that,

0

2/3

,H

h

h

L

h

sfunction

Q

Q B

B

B

B

B

L

C Eqn. 1

The suitability of Eqn. 1 as a design criterion was examined via extensive numerical modelling. The

model domain consisted of a single shore-parallel SBW placed on an alongshore uniform beach with

an equilibrium cross-shore profile. Based on over 100 Mike21 and Delft3D model simulations a

design criterion to determine the shoreline response to a shore parallel SBW is presented.

Keywords: Coastal protection, submerged breakwater, numerical model, Mike21, Delft3D



79

SECM/13/85

LIGHTWEIGHT MASONRY PRODUCTS FOR CONSTRUCTION ALONG THE COASTAL

AREAS OF PAKISTAN

1Abdul Bari Mangi,

2Muhammad Ghaffar

1Council for Works and Housing Research (CWHR), Pakistan



Abstract

This paper covers the R&D work carried out at the CWHR for developing lightweight solid and

hollow masonry products by using Lightweight Aggregate produced from raw shale of District

Lasbella Balochistan, Pakistan.

Shale is a basic raw mineral aggregate commonly obtained from different mining and quarrying areas

of District Lasbella Balochistan and along the vast coastal line. Shale as mineral aggregate or hard

mud silty stone can be bloated in rotary kiln to make lightweight expanded shale aggregate for

concrete construction at coastal areas of Pakistan. After conducting field survey along the coastal

areas of Balochistan, it is roughly estimated that trillions of metric tons of raw shale material is

available that can be utilized for making lightweight building materials including masonry blocks.

The CWHR as per scope of R&D works the ASTM C 90 for hollow lightweight load bearing concrete

masonry units and ASTM C 129 were referred for making hollow lightweight non load bearing

concrete masonry units for construction of all types internal and external walls with solid lightweight

concrete masonry products developed as per BS 2028 and ASTM C 140. The CWHR has developed

both lightweight concrete masonry units for utilization of waste shale material for coastal line of

Balochistan having large radius upto 650 km including coastal areas of Sindh also more than 350km.

The technical paper evaluates physical, chemical and mechanical properties of raw materials used for

preparation of lightweight masonry products that can be used at coastal areas of Pakistan and also

would be beneficial for arid, tropical and marine environments in different construction activities.

The author discussed objective of the R&D works, experimental programme run in developing

lightweight building blocks confirming to local and international standards including ASTM C 90,

ASTM C 129, ASTM C 140 and BS 2028, etc., results and discussion can be practically adopted at

the area identified.

Keywords: Raw material; Coastal Areas of Pakistan; Lightweight Aggregate; Expanded Shale;

Masonry Lightweight Blocks; Cost Effective Housing; Environment Friendly Building Materials.


80

SECM/13/86

STRUCTURAL ASSESSMENT OF SCHOOL BUILDINGS FOR POSSIBLE EARTHQUAKE

LOADINGS IN SRI LANKA

1P.A.K. Karunananda,

2K.Rathishkuamr,

3H.W.I.Prabath

1Department of Civil Engineering, The Open University of Sri Lanka, Nawala, Nugegoda





Abstract

Earthquakes are the most unpredictable natural hazards in the world. Sri Lanka, though located away

from major tectonic plate boundaries, has experienced significant number of earthquakes in the recent

past. Main function of a school building is to give room to teach to young generations. Apart from

that, school buildings provide space to various activities such as community meetings, cultural

functions, examination centre, election voting booth, and disaster recovery centre/refugees camps. In

the design stages of school buildings, earthquake loads are not presently considered. However, some

relevant institutes such as Sri Lankan National Building Research Organization (NBRO) state that

earthquake resisting structures should be introduced soon to our general practice of reinforced

concrete design. This paper presents the findings of a structural survey of existing school buildings in

Western Province of Sri Lanka for possible earthquake scenarios.

From earthquake history of Sri Lanka, it was found that there is a possibility of magnitude 6

earthquakes occurring with a return period of 100 years. Therefore, school buildings were analyzed

for magnitude of 6 earthquake loadings. In the non-availability of recorded earthquake loadings in Sri

Lanka, earthquake loading history reported in The Pacific Earthquake Engineering Research Center

(PEER) ground motion database was used. Further, General purpose SAP2000 v12.0 structural

analysis software package was utilized in time history analysis. It was found that slab members of the

buildings are the most critical members for the considered earthquake loadings. Provided

reinforcement amount is not sufficient to withstand an earthquake loading of magnitude of 6.

Therefore, it is needed to introduce some structural strengthening modifications to existing school

buildings to withstand moderate earthquake loadings in future.

Keywords: School buildings, Structural analysis, Earthquake loadings



81

SECM/13/88

HARDNESS BASED NON DESTRUCTIVE METHOD FOR DEVELOPING LOCATION

SPECIFIC S-N CURVES FOR FATIGUE LIFE EVALUATION

Chaminda S. Bandara1, Sudath C. Siriwardane

2, Kamal Karunananda

3, Udaya I. Dissanayake

4,

Ranjith Dissanayake5

1,4,5

Department of Civil Engineering, University of Peradeniya

Telephone: 0094-81-2388827


2Department of Mechanical and Structural Engineering and Material Science, Faculty of Science and

Technology, University of Stavanger, N-4036 Stavanger, Norway


3Department of Civil Engineering, Open University of Sri Lanka, Nawala


Abstract

This paper first describes the importance of using location specific S-N curves for fatigue damage

assessments of existing steel structures. It discusses the existing concepts and methods for developing S-N

curves using empirical formulae and monotonic strength parameters such as the ultimate tensile strength,

Brinell hardness and Vickers hardness. It also discusses relationships between these monotonic parameters.

Then it presents formulae for developing hardness based full range S-N curves for medium strength steels.

The formulae are verified using experimental data obtained from both monotonic and cyclic testing. Finally

it describes the advantages of these hardness based formulae for developing location specific S-N curves.

Keywords: Stress life curve, fatigue life, hardness, steel structures, non destructive test


82

SECM/13/89

MODELING OF CHARGE DENSITY EVOLUTION AND PIEZOELECTRICITY OF

FERROELECTRETS

D. Gross1, B. Xu

2, H. von Seggern

3, S. Zhukov

4

1Department of Civil Engineering & Geodesy, TU Darmstadt, Germany.

Telephone: +49 6151 162973; Fax: +49 6151 163018


2Department of Material Science, TU Darmstadt, Germany

Telephone: +49 6151 164373; Fax: +49 6151 166023



Telephone: +49 6151 166300; Fax: +49 6151 166305



Telephone: +49 6151 166250; Fax: +49 6151 166305


Abstract

Ferroelectrets, known as electrically charged micro-porous foam, have a very large longitudinal

piezoelectric effect and have received wide applications as sensors particularly in pressure sensor and

acoustical devices. During a charging process electric breakdown (Paschen breakdown) may take

place in the air pores of the foam and introduce free charge pairs, which can be separated by

electrostatic forces and relocated at the interfaces between the polymer and the electrically broke-

down medium. The development of this free charge density along the interfaces is the key for the

piezoelectricity of ferroelectrets. In this article, an internal variable based model is proposed to

simulate the hysteresis curve of the charge density development at the interfaces. Furthermore, a

Maxwell stress based electromechanical model is used for the bulk behaviour, i.e. the polymer and the

medium where the Paschen breakdown takes place. The models are presented in the framework of

finite deformation, which enables the possibility of taking into account the influence of deformation

change on the piezoelectricity. As an example, a ferroelectret unit with porous expanded

polytetrafluoroethylene (ePTFE) surrounded by fluorinated ethylene propylene (FEP) is simulated.

The simulated hysteresis curves of charge density at the interfaces, as well as the calculated

longitudinal piezoelectric constant, show good agreement with experimental results. To further

disclose the properties of the ferroelectrets, numerical investigations are conducted to study the

influence parameters on the hysteresis and the piezoelectricity, e.g. geometry, elastic properties and

the applied voltage.

Keywords: Pressure sensor, Piezoelectricity, Electroactive Foam, Charge Evolution




83

SECM/13/90

COMPARATIVE MODELLING OF INFILLED FRAMES: A DESCRIPTIVE REVIEW AND

ANALYSIS

S.H.Buch1

1Department of Civil Engineering, Islamic University of Science and Technology, India

Telephone: +91-9469153304


Abstract

Infilled frames are most common as of today. However, the general analysis is performed only for frame

action without considering effect of infills. The reason is that the behavior and action of infill frame is more

complicated than bare frames. Moreover, the structural and material parameters also vary greatly in infilled

frames.Infill is made of different materials, usually brick, block and stone masonry while as frame is usually

made of steel and reinforced concrete.

A review of various modelling techniques is done which are descriptive, defining various experimental and

mathematical techniques of infill frame modelling. The various mathematical macro-models and micro-

models for infill frames are compared with the experimental models for their behavioral action. This

comparison is done on bay frames which are studied for strength, stiffness, cracking pattern and mode of

failure under in-plane and vertical loads. The feasibility study of each model is performed for single bay

space frame. A deterministic flow-chart is finally generated which describes the modelling and analysis

methodologies and reports the effective modelling and analysis technique.

Keywords: Behavior, Frame, Infill, Modelling, Stiffness, Strength.


84

SECM/13/91

NOVEL PREPARATION OF NANOSIZED HYDROXYAPATITE/POLY(METHYL

METHACRYLATE) NANOCOMPOSITE FROM CALCIUM SUCRATE

W.P.S.L. Wijesinghe1, M.M.M.G.P.G. Mantilaka

2, R.M.G. Rajapakse

3, R.P.V.J. Rajapakse

4

1Department of Chemistry, University of Peradeniya, Sri Lanka

Telephone: +9471 5804927



Telephone: +9471 9398233



Telephone: +9481 2394442


4Department of Veterinary Pathobiology, University of Peradeniya, Sri Lanka

Telephone: +94 0714446715


Abstract

Hydroxyapatite (HA) nanoparticles and their polymer nanocomposites are extensively used in biomedical

fields, catalysis, chromatographic techniques and in water purification. Therefore, design and development

of low-cost and industrially applicable novel methods are essential to synthesize HA nanoparticles. In this

paper, we report such an economical, simple and industrially applicable novel method to synthesize

nanosized HA and HA-poly(Methyl methacrylate) (HA-PMMA) composite particles. In this method, the

HA has been synthesized by allowing to react disodium hydrogen orthophosphate with calcium sucrate. The

synthesized products are characterized by X-ray diffraction (XRD), Fourier Transform Infrared

spectroscopy (FTIR), Scanning Electron microscopy (SEM) and thermal analytical techniques to compare

with commercially available HA nanodispersion for the confirmation of quality requirements. The average

particle size of HA and HA-PMMA, as estimated from XRD, are 10 nm and 11 nm respectively. As

investigated, the synthesized HA products are in better quality and purity to meet with industrial and

commercial requirements.

Keywords: hydroxyapatite, poly(Methyl methacrylate), calcium sucrate, nanoparticles






85

SECM/13/92

RAIN WATER HAVESTING IN URBAN BUILDINGS

Gayani Karunasena1, Harshini Mallawaarachchi

2, Gunasekara J.D.E.M.


Telephone: 077-7220877 Fax:0112650738



Telephone: 071-2201158 Fax:0112650738



Abstract

Scarcity of water for human needs is prevalent throughout the world today. Thus, many methods are

being suggested to save water; one alternative being rainwater harvesting. Rainwater harvesting is an

ancient and most popular green building technique applied worldwide because of its effectiveness. Sri

Lanka has a long history associated with rainwater harvesting. The recorded history of hydraulic

civilization dates back to 5th century B.C. Large number of reservoirs, tanks, dilapidated irrigation

structures and inscriptions stand testimony to the dynamics of our hydraulic civilization. To date, this

traditional technique is implemented island wide, especially in rural areas with the new name of

rainwater harvesting. Mostly urban buildings need to be considered on the ways to save water as

solution for water scarcity and high utility bills in urban buildings. Hence, most of the buildings have

been tended to be greener to make their buildings more sustainable. However, the number of urban

buildings which has applied those techniques, especially rain water harvesting systems is considerably

low. Thus, this study aims identify rainwater harvesting systems in urban areas and investigate the

factors that affect the effective rainwater harvesting system. Comprehensive literature review was

conducted for data collection and professionals from both private and public sector involving

rainwater harvesting were interviewed to evaluate the different views on urban rainwater harvesting.

The study revealed technical, economical, environmental and operational factors that influence design

and implementation of effective rainwater harvesting system. Consequently, the study is enabled to

explore the current status of the urban rainwater harvesting and highlights the strengths and weakness

of the identified factors for successful implementation of urban rainwater harvesting system in Sri

Lanka.

Keywords: Rainwater harvesting, Factors, Urban buildings, Sri Lanka


86

SECM/13/93

SYNTHESIS AND CHARACTERIZATION OF POLYANILINE-MERCURY-

MONTMORILLONITE CLAY NANOCOMPOSITE

K.G. Chathuranga Senarathna1, , H.M.N. Bandaraa,

2 B.S.B.Karunaratne

3, R.M.G. Rajapakse

4

1Department of Chemistry , Department of Chemistry, University of Peradeniya, Sri Lanka.

Telephone: +94715521212


2 Department of Chemistry , Department of Chemistry, University of Peradeniya, Sri Lanka.

Telephone: +94 81 2394441


3 Department of Physics , Department of Chemistry, University of Peradeniya, Sri Lanka.

Telephone: +94 81 239 4598


4 Department of Chemistry , Department of Chemistry, University of Peradeniya, Sri Lanka.

Telephone: +94 81 2394442


Abstract

Mercurous cation-exchanged montmorillonite clay was prepared by exchanging interlayer cations of

purified montmorillonite for Hg22+

cations. The Hg22+

cations present in mercurous cation-exchanged

montmorillonite clay are used to oxidatively polymerize aniline in nitric acid solution to result in a

nanocomposite containing conducting polyaniline (PANI) nanofibers, mercury metal (Hg) nanoparticles

and exfoliated montmorillonite clay platelets. Although the noble metal PANI nanocomposites have already

been prepared, this is the first report for the preparation of Hg/PANI nanocomposites. The nanocomposite

PANI-Hg-MMT was characterized by X-ray diffraction (XRD), Fourier transform infrared

(FTIR)spectroscopy, thermo-gravimetric analysis (TGA), elemental analysis, X-ray fluorescence studies,

differential scanning calorimetry (DSC), electrochemical methods, DC conductivity measurements and by

AC impedance measurements. XRD patterns of composites depict that MMT layers exfoliated in the PANI

matrix. Electronic conductivity of PANI has been enhanced from that of PANI prepared using persulphate

as the oxidizing agent. This is due to mercury nanoparticles deposited on PANI chains. The mechanical and

thermal stability have also been improved from those of neat polymer or metal due to the incorporation of

montmorillonite clay. Even though this advanced material can be used to various application such as in

electronic sensors, the toxicity of mercury should be a prime consideration when using these materials in

technological applications.

Keywords: Polyaniline, montmorillonite, mercury, Nanocomposite, conducting polymer


87

SECM/13/94

DRAG FORCE ACTING ON A RECTANGULAR CYLINDER AND BED SHEAR STRESS

DUE TO OVERTOPPING FLOW FROM EMBANKMENT

J. Yagisawa1, N. Tanaka

2

1Institute for Environmental Science and Technology, Graduate School of

Science and Engineering Saitama University, Japan

Telephone: +81-48-858-3567


2Institute for Environmental Science and Technology, Graduate School of

Science and Engineering Saitama University, Japan


Abstract

At the Great East Japan earthquake tsunami, many houses were broken and washed out by the supercritical

tsunami flow overflowed from sea or river embankment. Under the supercritical flow, drag force

characteristics of dense obstacles and bed shear stress around them have not been clarified. Therefore, the

objective of this study is to find out the effect of spacing of neighboring obstacles on the drag characteristics

of rectangular cylinder (house model) and bed shear stress distribution around them.Drag force acting on the

house model and bed shear stress were measured by force gauge and shearing strain sensor, respectively.

Experiments were conducted for four cases of different overflow depth and three cases of different G/bh

(where, G and bh is horizontal spacing of each house model and width of a house model, respectively).

Drag force acting on the house model and bed shear stress between two house models (τm) increased with

narrowing G. When G/bh was 0.4, drag force and τm became 1.6 and 1.4 times comparing with single house

model, respectively. However, when G/bh was larger than 1.2, drag force and shear stress became almost the

same with single house case.

Keywords: drag force, bed shear stress, emerged rectangular cylinder, supercritical flow


88

SECM/13/95

ZONATION PATTERN OF MANGROVE IN SOUTHERN SRI LANKAN LAGOONAFTER

HUMAN INTERVENTIONS AT LAGOON MOUTH AREA

G.A.H.S. Chathuranga1, E. Furusato

2, G.L. Perera

3, N. Tanaka

4,5, T. Priyadarshana

6

1Graduate School of Science and Engineering, Saitama University, Japan

Telephone: +80-350-7494



Telephone: +48-858-3561



Telephone: +80-967-61986


4Institute for Environmental Science & Technology, Saitama University, Japan


Telephone: +48-858-3564; Fax: +48 858 7374


6Faculty of Fisheries and Marine Sciences & Technology,

University of Ruhuna, Matara (81000), Sri Lanka

Telephone: +94 (0)41 2222681 - 4501; Fax: +94 (0)41 2227026


Abstract

Growth of human population expands over vital ecosystems that is an inevitable phenomenon

throughout the world and equally valid to Sri Lanka. As a result of intense modifications to coastal

areas with different coastal structures creates number of ecological problems that can be monitored in

space and time. The present investigation was aimed to find out the impact of modifications made to

the mouth of Koggala lagoon on the natural dispersion pattern of true mangroves that can be affected

to the zonation of mangroves. After the removal of natural sandbar and construction of groyne at the

lagoon mouth has led to a significant salinity change in the lagoon. Therefore, salinity variation across

the lagoon was measured and mangrove zonation was mapped during the field surveys. High salinity

values (20 - 25 ppt) attributed to the increased intrusion of sea water was detected due to permanently

opened lagoon mouth. This can be directly attributed to the invasion of high salinity tolerance species

from lagoon mouth region to upper region, which was only limited to lagoon mouth region before the

construction of the groyne. Invasion speed of mangroves into the upper region can be determined by

the ability of propagule dispersal with respect to the species of mangrove and the establishment ability

of the location which both of these factors are important to assess during the planning process of

coastal structures. This paper emphasise the importance of possible ecological changes due to

modification of natural coastal settings by manmade structures which can be led to a long-term

negative impacts to ecology and stability of local economy.

Keywords: Coastal structures, lagoon, salinity variation, large scale zonation of mangroves





89

SECM/13/96

INVESTIGATION OF INDICATORS AND BENCHMARKS IN SOCIO-ECONOMIC

FACTORS IN SUSTAINABLE CONSTRUCTION FOR SRI LANKAN CONTEXT

A.M.D.C. Amarakoon1, S.R.Chandrathilaka

2







Abstract

“Sustainability” has become renowned and controversial topic throughout last decade considerably.

This concept basically lies upon three simple components Environment, Social and Economic trio.

According to prevailing conditions Environment component investigate more over other duo, with

consecrate minor consideration or neglected. Primary reason for neglecting those duo facts can be

demonstrate as immeasurable quality of those dual closely coupled components, Social and Economic

As mother institute in sustainability World Green Building Council (WorldGBC) initiate theoretical

framework for assess the social and economic components as major step toward assess this key area

in sustainable construction.

First version of green building rating system in Sri Lanka, GreenSL®

Version 1.0 also consecrate minor

consideration to these social and economic components considerably. When adapting WorldGBC

framework, local indicators and benchmarks should be developed taking into account the context and

conditions of Sri Lanka so as to harness the maximum potentials from the original framework

Availability of few experts in the field of sustainable construction and the availability of benchmarks

emerge as major limitation factors thus the concept is extremely important in assessing the green

buildings globally. This empirical research is began with the framework developed by the WorldGBC

with the craftsmanship of experts from 14 countries considering as the base, followed by a

comprehensive literature survey. Next lap of the process would be the preliminary questionnaire

survey which would support in determining the indicators and then expertise interviews would be

carried out to attain inputs from local practitioners to develop local benchmarks. Finally, the revised

framework addressing the social and economic factors would be readily available to be merged with

the existing Sri Lankan framework, GreenSL®

.

Keywords: Sustainability, Sustainable Construction, Social and Economic, Theoretical Framework,

Indicators and Benchmarks



90

SECM/13/97

DESIGN, ANALYSIS AND FABRICATION OF A FORMULA SAE CAR CHASSIS

Rajat Gupta1, Prateek Bansal

2, Rishabh Agrawal

3

1Department of Mechanical Engineering, Indian Institute of Technology Delhi

Telephone: +91-7709339390


2Department of Civil Engineering, Indian Institute of Technology Delhi

Telephone: +91-9645999897


3Department of Civil Engineering, Indian Institute of Technology Delhi

Telephone: +91-9910995889


Abstract

The Formula Society of Automotive Engineers (FSAE) organizes the most sought after technical events in

the university circuits participated by hundreds of universities across globe providing a highly competitive

platform to conceive, design and fabricate a formula style vehicle. In order to design and fabricate the space

frame chassis for such a vehicle, there exist an important structural design challenge while adhering to the

guidelines of SAE council. The present work serves as a guide to various universities entering into the

competition to understand the analytical design methods involved in building a chassis.

The design of a chassis is a complex process involving various inter-dependent sub-systems like Steering,

Engine, Drivetrain and Suspension, and the consequent temporally dispersed design informational inputs

from them. This paper describes a solution to the complexity with a 4 step methodology of design, analysis,

prototyping and fabrication. Essential design considerations were to achieve the shortest load path, optimal

triangulation at high load points, weight minimization and avoiding engine as a stress member. A 95th

percentile American male CAD model was developed in SolidWorks and used for subsequent design of

cockpit keeping driver ergonomics and safety in mind. Later front and rear chassis were designed using

steering-suspension and engine-drivetrain-suspension parameters respectively. The longitudinal lengths of

front, cockpit and rear chassis were decided according to the wheelbase and overhang. The design was

validated using Finite element analysis of the structure in ANSYS by subjecting it to the worst case loading

conditions experienced by vehicle during the race like braking, acceleration and cornering. The maximum

deflection (1.32 mm) and torsional rigidity (391.88 N.m/deg) was determined and found to be in acceptable

limits. This was followed by validation using a low cost prototype leading to minor design modification.

Thereafter the actual fabrication was carried out with the help of jigs and fixtures within acceptable

precision limits (±10 mm). The design was appreciated at event by judges as well as participants for its

compactness within the constraints.

Keywords: Wheelbase, Overhang, Prototype, Finite element analysis, Torsional rigidity, fixtures

http://www.mae.ncsu.edu/klang/courses/mae442/Motor%20Sports/Steel%20Chassis.pdf




91

SECM/13/98

EXPERIMENTS ON THE COLLIDING DURATION BETWEEN A DRIFTWOOD MODEL

AND A WOODY HOUSE MODEL FOR THE ACCURATE ESTIMATION OF THE IMPACT

FORCE BY TSUNAMI-DRIVEN WOODY DEBRIS

K. Ogino1, I. Suzuki

2, N. Tanaka

3

1Department of Civil & Environmental Engineering, Saitama University, Japan.

Telephone: +488583564; Fax: +488587374



Telephone: +488583564; Fax: +488587374



Telephone: +488583564; Fax: +488587374


Abstract

Coastal forest has a role to reduce a hydrodynamic force of tsunami, however it also produces driftwood and

increases the hydrodynamic force on houses by colliding on them. Previous study estimates the collision

force by numerical simulation, but it highly depends on the contact time of driftwood and a house.

However, there are few studies regarding the contact time and collision force due to a driftwood. Therefore,

the purpose of this study is to clarify the driftwood behavior and the collision force due to driftwood in

steady flow by flume experiment. A house modelwas set in a flume, and a driftwood model was supplied

from 1.5 m upstream of the house model location. Collision force and colliding duration were measured

directly by force gauge. The colliding duration was not much changed with the mass of driftwood, and the

impulsive fore was almost proportional to the mass, indicating the applicability of the impulse-momentum

approach. Moreover, actual collision time was calculated from the Froude similarity rule using the observed

collision time. The evaluated collision time was around 0.3 s, a little smaller value in comparison with the

standard value (1.0 s for the collision of wood and wood) recommended by FEMA(2008).

Keywords: Tsunami, Floating debris, Impulsive force, Colliding duration


92

SECM/13/99

PROPERTIES OF CONCRETE PAVING BLOCKS MADE BY USING BOTTOM ASH AS A

PARTIAL REPLACEMENT OF NATURAL SAND

N.G.N.Erandi1, W.C.Sakunthala

2, K.M.L.A.Udamulla

3.

1Department of Civil Engineering, The Open University of Sri Lanka, Nawala, Nugegoda,Sri Lanka.

Telephone: +94 716 324095


2Department of Civil Engineering, The Open University of Sri Lanka, Nawala, Nugegoda, Sri Lanka.

Telephone: +94 716 355308


3Department of Civil Engineering, The Open University of Sri Lanka, Nawala, Nugegoda,Sri Lanka.

Telephone: +94 771 388029; Fax: +94 11-2881616


Abstract

Disposal of bottom ash that is generated in huge quantities from thermoelectric power plants is a

major problem globally in general and Sri Lanka in particular. Several attempts exist to augment its

beneficial use. An attempt has been made to utilize this material for manufacturing concrete paving

blocks. This paper presents an experimental investigation carried out on the potential for using bottom

ash, i.e. the coarser material, which falls into furnace bottom in modern large thermal power plants

and constitute about 20% of total ash content of the coal fed in to the boilers, as a partial substitute

material for fine aggregate (sand) in the production of concrete paving blocks for road paving. The

paving blocks were cast by varying aggregate - cement ratios by replacing sand with bottom ash in

percentages of 0%, 25%, 50%, 75%, and 100%. The physical and mechanical properties, viz., water

absorption, density, compressive strength, and unpolished slip resistance value of the test specimens

were measured. The test results show that the concrete paving blocks with 25% of bottom ash

replacement by the mass of sand (at aggregate - cement ratio of 3.5) achieved the standard values of

properties as prescribed in the Sri Lanka Standard 1425 : part1:2011, specification for concrete paving

blocks : part 1- requirements. The results from this research suggest that the bottom ash can be

applied as a partial substitute for fine aggregate in concrete paving block production. Therefore, the

study will help reducing the usage of depleting resources by reducing the use of sand, and minimizing

environmental hazards through waste disposal by making use of bottom ash.

Keywords: Concrete paving blocks, Bottom Ash, Compressive Strength, Water Absorption, Unpolished slip

resistance


93

SECM/13/100

CALCIUM NITRATE MIXED CEMENT BASED MORTAR FOR REPAIRING CORRODED

RC STRUCTURES

B.H.J. Pushpakumara1, Sudeera De Silva

2, G.H.M.J. Subashi De Silva

3

1Department of Civil & Environmental Engineering, Faculty of Engineering, University of Ruhuna,

Sri Lanka

Telephone: +94-077-2206662; Fax: +94-091-2245762



Sri Lanka

Telephone: +94-091-2245765; Fax: +94-091-2245762



Sri Lanka

Telephone: +94-091-2245765; Fax: +94-091-2245762


Abstract

Chloride induced corrosion of embedded steel reinforcement is a one of the major deterioration modes

of Reinforced Concrete (RC) structures. Concrete and mortar are commonly used to repair the

corrosion damaged area. Use of corrosion inhibiting materials with repair compounds would minimize

further corrosion. Calcium nitrate is commonly used with concrete as a corrosion inhibitor. The

objectives of this study are to evaluate the efficiency of calcium nitrate based repair mortar for

corroded RC structures and to find out the optimum dosage of calcium nitrate.

Repair mortar mixes with calcium nitrate dosages varying from 0% to 25% by the mass of cement in

steps of 5% were used in the investigation. Six numbers of RC beams were cast and subjected to

Accelerated Corrosion Test Method (ACTM) until initiation of corrosion crack was detected.

Possibility of corrosion was evaluated by measuring resistivity using Resistivity meter. Corroded RC

beams were covered by using 10 mm thick calcium nitrate based repair mortar. The beams were again

subjected to ACTM for accelerated corrosion until the onset of 0.2 mm wide corrosion crack. The

efficiency of repair mortars was evaluated by measuring free and total chloride ions, rust production

(i.e., rust weight and bar diameter reduction) and possibility of corrosion by measuring resistivity.

Rapid Chloride Permeability Test (RCPT) was conducted to evaluate the chloride permeability of

repair mortars. Test results show that 10% of calcium nitrate effectively minimizes further corrosion

of reinforcement in concrete beams.

Keywords: Corrosion, Repair mortar, Calcium nitrate, Chloride concentration, Resistivity


94

SECM/13/101

SEISMIC RESISTANT TECHNIQUES FOR RETROFITTING OF EXISTING MASONRY

DWELLINGS IN SRI LANKA

W.S. Wasundara Mendis1, G.S.Y. De Silva


3

1Department of Civil and Environmental Engineering,

Faculty of Engineering, University of Ruhuna, Sri Lanka











Abstract

In Sri Lanka, unreinforced masonry has possessed a deep seated view in local culture since ancient

time, although unreinforced masonry is the most vulnerable against earthquakes. Sri Lankans have

experienced with minor earth tremors in and near the country region, since December, 2004. People

have been increasingly affected by these tremors within last year. In addition, an earthquake occurred

in Colombo area in 1615, has caused around 2000 of human deaths. It reveals that, the need of

introducing proper techniques for retrofitting of unreinforced masonry buildings, specially existing

buildings is time essential. Objective of this study is to evaluate, as first step, possibility of selected

and proposed seismic resistant techniques against static in-plane shear load. External bamboo strip

mesh, external Poly Propylene (PP) band mesh, ferrocement belts and diagonal steel bracings were

considered as suitable and economical techniques to increase seismic safety of existing masonry

structures in Sri Lanka.

Masonry walls having the size of 570 x 570 x 225 mm were cast using burned clay bricks and mortar

(i.e., cement: sand ratio 1:6) with English bond pattern, which are commonly used in masonry

buildings in Sri Lanka. The masonry walls, with and without retrofitting, were tested under static

diagonal compression test according to ASTM-E-519-02 standard guidelines with using 200 kN

hydraulic actuator. Test results indicated that, retrofitting of URM walls with bamboo strip mesh and

PP-band mesh could be an effective and reliable strengthening technique and those methods may be

economical. Although, the wall with ferrocement belts collapsed, this technique capable of

dissipating some energy, redistributed the load and showed considerable visual clues before collapse.

Retrofitting of masonry wall with ferrocement belt is also good strengthening alternative technique.

Near surface mounted diagonally arranged twisted steel bracing is totally not reliable retrofitting

technique.

Keywards: Un-reinforced brick masonry, Seismic resistant, Diagonal shear test, In-plane load,

Retrofitting

95

SECM/13/102

UTILITY OF HYBRID MUTATION OPERATOR IN REAL CODED GENETIC

ALGORITHM FOR OPTIMIZATION PROBLEMS

C. Mohanlal 1 and N. Murali Krishna

2


Vasavi College of Engineering , Hyderabad – 500031,India




University College of Engineering, Osmania University, Hyderabad-500007, India



Abstract

Methods which modify the search strategies during the run of the genetic algorithm are always

desirable as they could simultaneously lead to improvementsin its performance. With an attempt to

alter the search strategies, a modified genetic algorithm using hybrid mutation operator is presented in

this paper to investigate its suitability for a set of mathematical test functions and a few structural

design problems. The objective of introducing hybrid mutation operator here is to widen the

population diversity so as to avoid its premature convergence. Objective functions with constraints are

used for the optimization of the mathematical expressions. The objective function used for structural

design problems minimizes the weight of the truss structures with constraints imposed by strength and

serviceability criterion. The utility of the study is demonstrated by comparing the results obtained

from the current formulation with the earlier research works and some useful conclusions are

presented.

Keywords: Optimization, Genetic Algorithms, Real coding, Mutation, convergence.



96

SECM/13/103

THE EFFECT OF SEISMICITY ON SIGN BOARD GANTRIES OVER NATIONAL ROADS

T. N. Haas1, F. Albertyn

2

1Department of Civil Engineering, Stellenbosch University, South Africa.

Telephone:27 021 808 438; Fax:27 021 808 4947


2 Department of Civil Engineering, Stellenbosch University, South Africa.

Telephone:27 021 808 438; Fax:27 021 808 4947

Abstract

South Africa is at risk to low intensity seismic activity. In these regions no special analysis is

required. There are however certain regions in South Africa which are at risk to moderate seismicity.

Infrastructure in these regions must be designed to comply with the relevant national standards.

Included in this infrastructure are sign board gantries which cross over the national roads. The

configuration of these sign board gantries is standard with respect to; section sizes, the number and

diameter of the holding down bolts. It is believed that these structures were designed by only

considering wind load. This uncertainty lead to investigating whether these sign board gantries could

sustain a moderate intensity seismic event. Of particular interest to this investigation was to determine

whether the holding down bolts could withstand the base shear forces generated by a moderate

intensity seismic event. The investigation was conducted using Finite Element Analysis by subjecting

U and L shaped sign board gantries to various ground accelerations. The results from the investigation

revealed that both U and L shaped sign board gantries are able to withstand a moderate intensity

seismic event. The number of holding down bolts is conservative and thus uneconomical in its present

state.

Keywords: Earthquake, Sign board gantries, Finite Element Analysis


97

SECM/13/104

SIMULATIONAND MEASUMENT OF WEB GAP STRAIN IN A STEEL GIRDER FOR

DEVELOPING A SHM SYSTEM– A LABORATORY STUDY

U. B. Attanayake1

1Department of Civil & Construction Engineering, Western Michigan University, USA.

Telephone: 269-276-3217; Fax: 269-276-3211


Abstract

The stress developed at specific details of multi-girder steel bridges under repeated loading (fatigue)

is a concern. The majority of the details that are prone to fatigue are identified and classified in the

design specifications. Whether the detail is classified or not, there are certain configurations which

lead to unintended distortion. As a result, the stressesdeveloped at such details are not accounted for

the design. Even though these secondary stresses are not accounted for in the design, some of these

details develop high stress under fatigue leading to cracking. Hence, it is vital to instrument such

details with an objective of (1) monitoring stress for calculating fatigue life and (2) detecting stress

waves that are generated due to fatigue crack initiation and growth.

This article discusses the state-of-the-art technologies available for developing a monitoring system to

achieve the above stated objectives related to distortion-induced fatigue, simulation of web gap strains using

laboratory specimens, and developing a strain gage configuration for measuring web gap strains as part of a

structural health monitoring (SHM) system.

Keywords: Acoustic emission (AE), Bridge, Distortion, Digital image correlation, Fatigue,

Monitoring


98

SECM/13/105

ARTIFICIAL NEURAL NETWORK FOR EVALUATING PRECAST ELEMENT

CONNECTION INTEGRITY

U. B.Attanayake1 , C. Mansiz

2

1Department of Civil &Construction Engineering, Western Michigan University, USA.

Telephone: 269-276-3217; Fax: 269-276-3211


2Department of Civil &Construction Engineering, Western Michigan University, USA.

Telephone: 269-276-3210; Fax: 269-276-3211


Abstract

The expectation is to develop bridges with service life of 100 years or more. Prefabricated bridge

elements and systems (PBES) are widely used to accelerate bridge construction because

prefabrication is expected to offer durable components or systems to build bridges with such a long

service life. However, field cast connections between PBES are the weakest link in terms of

durability. Hence, to develop durable bridges not only the use of durable PBES but also the use of

connection details and materials with a record of durable performance and implementation of the best

practices in construction, quality assurance/quality control (QA/QC), and maintenance are needed.

When a bridge with PBES is considered as a structural system, deterioration starts at the field cast

connections. Hence, it is vital to identify the onset of deterioration at connections before visual signs

are developed to initiate maintenance actions to be effective and efficient in arresting further

deterioration. When a bridge is considered, the deck is the shelter of the structure which is subjected

to severe loads due to exposure and traffic. Hence, detecting the onset of deck connection

deterioration is vital to ensure a long service life of a bridge. This paper presents an Artificial Neural

Network (ANN) based approach for detecting onset of precast component connection deterioration.

As a prototype, a full-depth deck panel system is used. The stress data recorded at a transverse

connection is used. The results are promising; however, need further investigations to establish the

distress thresholds.

Keywords: Artificial Neural Network, Deterioration, Embedded Sensors, Finite Element, Full-Depth

Deck Panel



99

SECM/13/106

A ROAD MAP FOR EFFECTIVE IMPLEMENTATION OF NONDESTRUCTIVE TESTING

INTO BRIDGE MANAGEMENT

U. B. Attanayake1, H. M. Aktan

2


Telephone: 269-276-3217; Fax: 269-276-3211



Telephone: 269-276-3206; Fax: 269-276-3211


Abstract

The highway agencies in the U.S. are entrusted to manage more than 600,000 bridges. To facilitate these

efforts, bridge management programs are developed. Bridge management programs are supported by the

information in databases such as Pontis. The Michigan Department of Transportation is one such agency

that uses data from Pontis for bridge management purposes. The state trunkline system managed by the

Michigan Department of Transportation (MDOT) comprised of 9,695 miles and carries 51 percent of total

statewide traffic. There are 4,413 bridges on the trunkline and 40 percent is on freeways. Total bridge deck

area maintained by the MDOT is 49 million square feet (i.e., 75 percent of the bridge deck area of all

Michigan‟s highway bridges). Michigan has eleven corridors on National/International significance. The

decision principles to guide the management, operation, and investments on these corridors include

strategies to reduce delays and minimize impacts during inspection as well as construction. One of the

strategies explored by MDOT is to incorporate and integrate NDE technologies to bridge management.

This paper presents an overview of the MDOT Pontis database, data collection process, implementation

ready nondestructive testing technologies suitable for collecting useful data for bridge management

purposes, and a road map to integrate such technologies into the bridge management program.

Keywords: Bridge, Bridge Management, Nondestructive Testing



100

SECM/13/107

AN APPROACH TO ESTIMATE FATIGUE LIFE OF OFFSHORE JACKET STRUCTURES:

A CASE STUDY

Redion Kajolli1, Sudath C. Siriwardane

1,Ranjith Dissanayake

2

University of Stavanger, Department of Structural & Mechanical Engineering and Material Science,

Stavanger N-4036, Norway

Telephone: +47-46790309


2

Department of Civil Engineering, University of Peradeniya, Sri Lanka


Abstract

Miner‟s rule is generally accepted as the fatigue criteria for life estimation of offshore steel structures.

Similarly, it has always been acknowledged as a simplification that is easy to use in design where detailed

loading history is unknown. But in the case of structures where the detailed loading history is known,

Miner‟s rule might provide incorrect results because of its omission of load sequence effect. Recently, a new

damage indicator-based sequential law has been proposed to capture the load sequence effect more

precisely. However, application of this sequential law to estimate fatigue lives of steel structures has not

been properly studied. Therefore, the major objective of this study is to estimate the fatigue life of an

offshore jacket structure using the sequential law. Hence a new approach to estimate fatigue life is

introduced. This approach is specially based on combination of wave induced stress histories at hot spot,

sequential law and fully known S-N curve.

Initially variable amplitude nature of waves was simulated by considering past records of wave heights and

theories in hydrodynamic. TheMorrison‟s Equation was employed to simulate wave structure interaction

(i.e. to obtain inertia and drag force histories of tubular members) of the jacket structure. Then FEM

employed time-history dynamic analysis was conducted to obtain force histories of each tubular legs and

braces of the jacket structure. The DNV codespecified guidelines were used to calculate stress concentration

factors for tubular joints. The superposition of stresses was done and hence hot spot stress histories were

determined. A technique is introduced to obtain the full range S-N curve for tubular joints and predicted

curve was illustrated. Then the sequential law was applied to obtain fatigue lives of two critical joints of the

jacket. Finally, the obtained fatigue lives were compared with previous method-based estimations (i.e.

Miner‟s rule based estimations) and about 20% reduction of fatigue life is recognized. Then applicability,

significance and validity of the used approach were discussed.

Keywords: Fatigue life; Wave-structure interaction; Time history dynamic analysis; Offshore jacket

structure





101

SECM/13/108

HYDROTHERMAL SYNTHESIS OF MAGNESIUM OXIDE NANOPARTICLES FROM

DOLOMITE AND REJECTED BRINES OF SALT INDUSTRY

M.M.M.G.P.G. Mantilaka1,H.M.D.D. Dasanayake

2,D.G.G.P. Karunaratne

3, R.M.G. Rajapakse

4,

H.M.T.G.A. Pitawala5


Telephone: +94 71 9398233


2Department of Chemical & Process Engineering, University of Peradeniya, Sri Lanka

Telephone: +94 71 9726462


3Department of Chemical & Process Engineering, University of Peradeniya, Sri Lanka

Telephone: +94 81 2393699



Telephone: +94 81 2394442


5Department of Geology, University of Peradeniya, Sri Lanka

Telephone: +94 81 2394211


Abstract

Magnesium oxide nanoparticles are increasingly used in construction industry, especially in production of

cement and concrete. Therefore, to fulfill the current demand of MgO nanoparticles, it is required to identify

readily available inexpensive raw materials and simple techniques for the production of these nanoparticles

in large-scale. Herein, we report a novel and low-cost method to synthesize MgO nanoparticles using

wasted brines of salt industry and widely distributed naturally occurring dolomite as raw materials. In this

method, 1.0 mL of triton X 100, a stabilizer is mixed with 39.0 mL of pretreated brine with a mixture of

barium chloride and dilutes nitric acid. 0.50 g of calcined dolomite (CaO.MgO) is added to the reaction

mixture and hydrothermally treated in an autoclave at 160 °C for 16 h to prepare magnesium hydroxide

precursor which is heated at 450 °C for 3 h to produce MgO nanoparticles. X-ray Diffraction (XRD)

analysis confirms the presence of periclase form of MgO with average particle size of 28 nm. The product is

further characterized by Fourier Transform Infrared (FTIR) spectroscopy, Atomic Absorption

Spectrophotometry (AAS) and Thermal analyses. As estimated, approximately, 9052 Mt/yr of MgO

nanoparticles can be synthesized from the proposed method using Sri Lankan brine and dolomite to fulfill

the current demand.

Keywords: Dolomite, Brine, magnesium oxide nanoparticles, Value addition, construction raw material







102

SECM/13/109

ENHANCED PERFORMANCE OF SRI LANKAN NATURAL GRAPHITE USING

ELECTROLYTE ADDITIVES

Nanda Gunawardhana1, L. P. Gamage

2, Jagath Gunatilake

3, Masaki Yoshio

4

1International Research Centre, University of Peradeniya, Sri Lanka

Telephone: 094-81-238-2401


2Postgraduate Institute of Science, University of Peradeniya, Sri Lanka

Telephone: 094-779299533


3Department of Geology, Faculty of Science, University of Peradeniya, Sri Lanka

Telephone: -094-81-238-4219


4Advanced Education and Research Centre, 1341 Yoga-mach, Saga 840-0047, Japan

Telephone: 081-952-20-4729


Abstract

Lithium-ion batteries (LIBs) have become one of the most important energy sources for portable electronics,

Hybrid Vehicles, Electric Vehicles and are starting to be used in air planes. Due to its high energy density,

high charge/discharge rate and availability in a wide temperature range, the demand has increased. Current

LIBs mostly consist of a graphite anode. Major reasons for using graphite are safety and thermal stability.

Now researchers have focused on natural graphite to create a high performance anode with high purity. Sri

Lankan Natural Graphite (SLNG) has various desirable structural and physical characteristics like high

purity (99.9%), extensive mineralization and high crystallinity, that are applicable for its use as anode

material for LIBs. The results of basic electrochemical tests indicate that SLNG shows a high capacity of

lithium intercalation with a better cycle life.

To enhance the performance of the charging rate, chemicals are added to the electrolyte known as additives.

Here selected additives for natural graphite are tested using different graphite samples. Computational

Calculations were performed to select proper additives for SLNG. Samples were prepared by considering

source and particle size and were collected from Bogala and Kahatagaha mines, then they were crushed and

sieved into different particle sizes. The electrochemical performance was tested and compared with and

without additives. The results of these experiments will be discussed in the presentation.

Keywords: Lithium Ion battery, Graphite anode, Additives, Natural Graphite, Crystallinity




103

SECM/13/110

SUSTAINABLE DEVELOPMENT WITH STEEL CONCRETE COMPOSITE STRUCTURES

STUDY ON THE FIRE RESISTANCE

Bui Van Hong Linh

Faculty of Civil Engineering, Ho Chi Minh City University of Technology, Vietnam.

Telephone: +841658202314


Abstract

Steel softens progressively from 100-200°C up. Only 23% of ambient-temperature strength remains at

700°C. At 800°C tensile strength reduced to 55%, at 900°C to 70% and melts at about 1500°C. Concrete

also loses compressive strength and stiffness from 100°C upwards and does not regain strength on cooling.

High temperature properties depend mainly on aggregate type used. The fire resistance class is normally the

same as that of the slab that acts as the top flange of the beam, so only the structural steel section needs

further protection. This may be provided by full encasement in concrete of a lightweight fire-resisting

material. A more recent method is to encase only the web in concrete. In a fire, the exposed bottom flange

loses its strength, but the protected web and top flange do not.

Fire resistance is expressed in units of time so one of the contributory factors to fire resistance is the

heating rate of the member. This governs the time taken to reach it‟s failure temperature and varies

according to the dimensions of the section. Composite construction therefore offers considerable

possibilities faced to those offered by traditional steel construction, be it in terms of fire protection or

otherwise to suit particular design criteria. The fire resistance that can be achieved using composite

construction has greatly contributed to its success, with the added advantage of being able to retain

exposed steel surfaces that can be used for attachments. The excellent ability of composite structures

to resist seismic loading is yet another advantage of this form of construction.Passive fire protection

materials insulate steel structures from the effects of the high temperatures that may be generated in

fire. They can be divided into two types, non-reactive, of which the most common types are boards

and sprays, and reactive, of which intumescent coatings.

Keywords: Fire resistance, thermo-mechanical properties, composite structures, sustainable construction.


104

SECM/13/111

DEVELOPMENT OF NANOTECHNOLOGY IN CONCRETE ENGINEERING

SOLUTION FOR SUSTAINABILITY

Bui Van Hong Linh


Telephone: +841658202314


Abstract

The majority of recent nanotechnology research in construction has focused on the structure of cement-

based materials and their fracture mechanisms. New advanced equipment makes it possible to

observe a structure at its atomic level. Atomic force microscopy has been applied to the

investigation of the amorphous C-S-H gel structure. This has led to the discovery that this product

has a highly ordered structure at the nanoscale. Understanding of nanoscale structure helps to

influence important processes related to production and use of construction materials, including

strength development, fracture, corrosion and tailoring of desired properties

.

The properties of concrete are improved by the use of nano powders, since nano particles fill the voids

between cement grains and also consume a part of calcium hydroxide which results in additional

formation of calcium silicate hydrate (C.S.H.) and more improvement of interface structure. The application

of nano SiO2 particles with newly developed super plasticizer improved the workability and strength of

high performance and self-compacted concrete since nano-SiO2 interpenetrates polymer network, and

causes the above improvements. The progress from sulphonated polymer to polycarboxylate has resulted

in higher water reduction at a given workability, lower slump loss and (43-48)% higher compressive

strengths, according to the indicated results. The efficiency of nano particles such as nano-Si02

depends on their morphology as well as the application of effective super plasticizers which help to

disperse formation of agglomerates and improve concrete strength. Nano particles, such as nano silica

dioxide (Nano-SiO2) were found to be very effective when mixed separately with super plasticizer

(polycarboxylate base) and then added to the 20 % remained of mixing water as mentioned in mixing

procedure. Nano-Silica concrete requires additional amount of water or super plasticizer to maintain

the same workability level. Nano-Silica addition results in significant increase in concrete compressive

strength after 28-days up to one year and the optimum amount of nano silica is 0.5% by weight of

cementitious material.

Keywords: Nanotechnology, Concrete, Microstruture, Nanosilica, Nano – composites, Nano-tubes.


105

SECM/13/112

CHARACTERISTICS OF BAMBOO FOR STRUCTURES ENVIRONMENTALLY

FRIENDLY IN RURAL VIETNAM

Bui Van Hong Linh


Telephone: +841658202314


Abstract

In Vietnam and other developing countries where reinforced concrete in construction is widely used,

the high and steadily increasing cost of steel has made construction very expensive. This development

has triggered off the search for alternative and suitable replacement for steel reinforcement in

concrete works. This search for a cheaper alternative has led to the exploration of abundant, naturally

occurring materials such as bamboo, coconut fibres, sisal and oil palm fibres which can be obtained

locally at low cost and low levels of energy using local manpower and technology.The use of these

locally available materials as substitute for the conventional materials in reinforced concre te elements

can cut construction costs by as much as between 30% and 80%. Interest in these local materials, they

are “eco-friendly” and the rising level of pollution in the construction industry has called for the

adoption of “Eco-structures”, which are constructions that are in harmony with the surroundings and

do not violate the environment neither through the chosen building materials nor through the

constructionmethods.

Bamboo is one of the oldest construction materials. Building with bamboo looks back on an ancient

tradition in the regions in which plant grows in abundance, such as South America, Africa and, in

particular, in South-East-Asia. The main area of distribution are the tropics, bamboo grow at sea-level

and can be found at altitudes of up to 3800m. Most bamboo species grow at temperatures from - 28°C

to + 50°C. Bamboos grow mainly on sandy loam to loamy clay soils. They prefer well drained soils

but grow also in wet and even marshy locations. They do not tolerate saline soils. The fibres of the

bamboo run axial. In the outer zone are highly elastic vascular bundle, that have a high tensile

strenght. The tensile strenght of these fibres is higher than that of steel, but its not possible to

construct connections that can transfer these tensile strenghs. This paper

presentstheclassificationcharacteristics, mechanical propertiesandconstruction methodof bamboo

component for structures environmentallyfriendly in rural Vietnam.

Keywords: Local materials, Bamboo structures, Rural in Vietnam, Green building.


106

SECM/13/113

RISK ASSOCIATED WITH NOISE AND VIBRATION EXPOSURES AND THEIR EFFECTS

ON HEALTH OF WORKERS IN CONSTRUCTION SITES

V.H.P.Vithrana1, G.H.M.J. Subashi De Silva

2, G.S.Y. De Silva

3

1Department of Civil & Environmental Engineering, University of Ruhuna, Sri Lanka

Telephone: 0712767575; Fax: 091-2245762



Telephone091-2245765-67; Fax: 091-2245762



Telephone: 091-2245765-67; Fax: 091-2245762


Abstract

Construction industry is one of main hazard industry due to the nature of activities involved in

construction. In Sri Lanka, there are several research works investigating this hazardous nature based

on statistical data analysis of death and injuries caused by the risk factor having acute effect such as

working in higher places. However, no attention has been paid on health effects of construction

workers due the risk factors having chronic effects such as noise and vibration exposures. Objective

of this study is to investigate risk associated with construction activities, noise and vibration exposure

levels in Civil Engineering Construction sites and their effects on the health of workers.

A questionnaire survey was conducted among workers in building construction sites in the Southern

Province, Sri Lanka. In addition, noise exposure was measured by using noise level meter while

vibration exposure was measured by using a seat pad accelerometer attached to tri-axial vibration

meter. The Relative Important Index (RII) was determined to rank risk factors. RII values for

“exposure to noise” and “exposure to vibration” were 0.22 and 0.21, respectively. It was found that,

although these two values indicate that the workers are less aware about risk of noise and vibration

exposures, exposing to severe noise and vibration for a prolonged time can lead to adverse health

effects. Noise and vibration exposure levels prevailing in construction sites and their effects on the

health of workers are discussed in this paper.

Keywords: Civil Engineering Construction sites, Construction worker, Noise, Vibration



107

SECM/13/114

A COMPREHENSIVE FRAMEWORK FOR WORKER PLANNING IN CONSTRUCTION

C.S.A Siriwardana1, J.Y. Ruwanpura

2

1Department of Civil Engineering, University of Calgary, Calgary AB T2N 1N4, Canada

Telephone: +15877005004


2Department of Civil Engineering, University of Calgary, Calgary AB T2N 1N4, Canada

Abstract

Workforce is the fundamental and critical concern in success or failure in a construction project;

however conventional construction practices have underutilized this important resource. This fact is

proved by observing productivity values of construction industry lagging behind the other industries

over the years. Therefore it may very well be the right time for a paradigm shift from conventional

work force management practices to innovative, creative and more technically sound best practices.

Based on McGrath (1964), Gladsetin‟s (1984) and Hackman (1987) Input-Process-Ouput models, this

paper is focusing on developing a comprehensive workforce management framework which provides

a holistic understanding of the relationship between tasks and people. Here the aim is to improve

productivity by eliminating waste and non-value adding activities by redesigning the work flow.

Furthermore this paper tries to present a methodology for systematic identification, evaluation, and

recognition of productivity improvement opportunities.

Keywords: Labour productivity, construction productivity, worker performance, pre-construction

planning, I-P-O models, workforce management


108

SECM/13/115

PROGRESSIVE COLLAPSE ANALYSIS OF REINFORCED CONCRETE FRAMED

STRUCTURE

Rakshith K G1, Radhakrishna

2

1 Department of Civil Engineering, RV College of Engineering, Bangalore.

Telephone: +919844469237


2Department of Civil & Engineering, RV College of Engineering, Bangalore.

Telephone: +919886127398


Abstract

The progressive collapse of reinforced concrete structures is initiated when one or more vertical load

carrying members are removed due to man-made or natural hazards. The building‟s weight transfers to

neighboring columns in the structure, leads to the failure of adjoining members and finally to the failure of

partial or whole structure system. In which the collapsing system continually seeks alternative load paths in

order to survive. In the present study the Demand Capacity Ratio (DCR) of reinforced concrete twelve

storey framed structure are evaluated as per U.S. General Services Administration (GSA) guidelines. The

Linear static analysis is carried out using software, ETABS V9.7. To study the structural behavior of the

building for progressive collapse, a finite element model is considered. Modeling is carried using the

preprocessing function of structural analysis program. Further loading are assigned to model according to

Indian Standard codes. Analysis and design is carried out for member forces and reinforcement details. The

column is removed from model to initiate progressive collapse and analysis is carried out for member

forces. From the analysis result DCR values are calculated. The obtained DCR values show that columns

are safe and beams to be reinforced additionally.The adequate reinforcement provided in extra to beams

which are unsafe can develop alternative load paths and prevent progressive collapse due to the loss of an

individual member.

Keywords: Progressive collapse, ETABS, Demand Capacity ratio, Finite element model.



109

SECM/13/116

ANALYSIS CHARACTERISTIC AND DESIGN METHODS OF MASONRY STRUCTURES

Bui Van Hong Linh


Telephone: +841658202314


Abstract

Masonry consists of a variety of materials. Raw materials are made into masonry units of different

sizes andshapes, each having specific physical and mechanical properties. Both the raw materials and

the method of manufacture affect masonry unit properties. The masonry is a general term that applies

to construction using hand-placed units of clay, concrete, structural clay tile, glass block, natural

stones and the like. One or more types of masonry units are bonded together with mortar, metal ties,

reinforcement and accessories to form walls and other structural elements. Proper masonry

construction depends on correct design, materials, handling, installation and workmanship. With a

fundamental understanding of the functions and properties of the materials that comprise masonry

construction and with proper design and construction, quality masonry structures are not difficult to

obtain.

Load-bearing masonry as a structural system is often in competition with frames of structural steel or

concrete as the primary structural system for a building. However, masonry is also used as an infill for

exterior walls of framed systems. The interaction of masonry with a frame often leads to construction

interferences, particularly with diagonal bracing in building frames. Masonry can be used in combination

with steel or concrete framed construction to create an efficient hybrid structure that uses the specific

qualities of each structural material. With the growing concerns for preventing progressive collapse and

building safety, reinforced masonry offers a renewed opportunity to provide structural redundancy when

used in combination with structural frames.This paper will introduce the concept of masonry structures,

framed construction used in combination with reinforced masonry, mechanical and physical characteristics

of masonry structures and design method for some cases.

Keywords: Masonry materials, Masonry structures, Steel concrete frames, Design masonry structures.


110

SECM/13/117

COLLAPSE ANALYSIS OF MULTI STRORIED REINFORCED CONCRETE FRAMED

STRUCTURE

Rakshith K G1, Radhakrishna

2

1Department of Civil Engineering, RV College of Engineering, Bangalore.

Telephone: +919844469237


2Department of Civil Engineering, RV College of Engineering, Bangalore.

Telephone: +919886127398


Abstract

The progressive collapse of any structure is initiated when one or more vertical load carrying members are

removed due to man-made or natural hazards. The load on the column destroyed transfers to neighboring

columns in the structure in turn leads to the failure of adjoining members. This unusual loads due failure of

column will cause partial or complete distortion of structure. The collapsing system continually seeks

alternative load paths due extra burden loads. In the present study, typical columns were removed and the

Demand Capacity Ratios (DCR) is calculated in a twelve storied reinforced concrete framed structure. The

analysis was carried out as per U.S. General Services Administration (GSA) guidelines. The Linear static

analysis was carried out using software, ETABS V9.7. Modeling was carried using the preprocessing

function of structural analysis program. Further loadings were assigned to model according to Indian

Standard codes. Analysis and design was carried out for member forces and reinforcement details. The

column was removed from model to initiate progressive collapse and analysis was carried out for member

forces. From the analysis the DCR values were calculated. The obtained DCR values show that columns

are safe and beams to be reinforced additionally for safety.The adequate reinforcement provided in extra to

beams which are unsafe can develop alternative load paths and prevent progressive collapse due to the loss

of an individual member. This is one of the methods to prevent the collapse in specified conditions.

Keywords: Progressive collapse, ETABS, Demand Capacity ratio, Finite element model.



111

SECM/13/118

EXPERIMENTAL STUDY OF WAVE TRANSMISSION AND POOL RESPONSE OF

SEAWALL DEFENCED BY A LOW-CRESTED BREAKWATER

M.G. Muni Reddy1, K. Srinivasa Reddy

2

1Department of Civil Engineering, Andhra University, Visakhapatnam, India.

Telephone:+91 9494572898 ; Fax: 0891-2791179, 2747969


2Department of Civil, LBR college of Engineering, Mylavaram, India.

Telephone: +91 9441887287


Abstract

Wave characteristics on seawall and a low-crested breakwater system were studied by a systematic

experimental programme in wave flume. The influence of the pool length on reduction of wave

transmission and the corresponding wave forces on the seawall was investigated. The main aim of

these tests was to know the effectiveness of offshore low-crested breakwater as a rehabilitation

structure for damaged seawall. Hydrodynamic performance of narrow and broad-crested rubble

mound breakwater with different relative breakwater heights was investigated in the present work.

A detailed experimental programme was carried out in a wave flume of 45m long, 1.2.0m wide 1.20m

deep at Department of Civil Engineering, Andhra University College of Engineering, Visakhapatnam,

India. Regular waves of different pre-determined wave frequency and wave amplitude combinations

are generated for the tests. The wave transmission from seaside to leeside of breakwater depends on

structural parameters as well as on the initial wave climate.

The wave elevations in the pool i.e., distance between the seawall and low-crested breakwater were

measured using a wave probes and it was observed that water elevations are highly random for the

regular incident waves. With the sections proposed in this study, it is possible to achieve considerable

reduction of wave forces on the seawall. The results obtained from the above experimental

programme will be discussed in detail in the full paper. Water surface elevations in the pool with

respect to relative water depth and wave steepness for different breakwater crest widths will also be

discussed in the full paper.

Keywords: Seawall, Low-crested breakwater, Wave transmission, Pool length, Wave forces.




112

SECM/13/119

MINIMIZING NON-VALUE ADDING ACTIVITIES IN CONSTRUCTION

PROCESSES USING LEAN TECHNIQUES

N. Thilakarathna1, Y.G. Sandanayake

2, S. Senaratne

3

1Department of Quantity Surveying, British College of Applied Studies, Sri Lanka



2Department Building Economics, University of Moratuwa, Sri Lanka


3University of Western Sydney, Australia.


Abstract

Lean is an innovative construction management approach which is linked closely to the overall life of

the project to ensure project success. Lean construction is still new to many construction industries in

the world. Activities in construction can be divided into two: conversion activities which produce

tangible and flow activities which bind such conversion activities during the delivery process of the

output.Lean Principles state that only conversion activities add value and these should be made more

efficient, whereas non-value adding flow activities should be reduced or eliminated. By eliminating

waste activities, processes can become „lean‟ which provide „more with less‟ resources. Research into

lean principles has found that considerable waste lies in flow processes of construction projects.

These flow wastes are recognized as a major weakness, which hinder performance of the construction

industry. However, the construction industry lacks an implementation framework to minimize the

non-value adding activities generate in construction processes.

Therefore, this paper investigates the different lean techniques developed in the manufacturing

industry and how these lean techniques can be applied to minimize the non-value adding activities

generate in different phases of construction. Further, paper presents a conceptual framework which

maps the lean techniques and non-value adding activities in construction processes. A comprehensive

literature review was used to develop the framework and it was further refined by an opinion survey.

Opinions were obtained from the construction specialists who have experience in implementing lean

techniques. The conceptual framework developed in this study illustrates the links between lean

techniques and non-value adding flow activities in different phases in construction processes in order

to minimize those using proposed techniques. The framework will be further tested and validated by

applying to a construction project during the next phase of this study.

Keywords: Non-value adding activities, Construction Processes, Lean Techniques




113

SECM/13/120

SOIL CHARACTERIZATION FOR THE DEVELOPMENT OF SITE-SPECIFIC

PERMEABLE REACTIVE BARRIER IN SRI LANKA: MINERALOGICAL AND SURFACE

CHARGE PROPERTIES FOR SELECTED SURFACE GEOLOGIC MEDIA

G. N. Paranavithana1, B.G.N. Sewwandi

2, and K. Kawamoto

3


Telephone: +81-48-858-4772; Fax: +81-48-858-7374



Telephone: +81-48-858-4771; Fax: +81-48-858-7374



Telephone: +81-48-858-3572; Fax: +81-48-858-7374


Abstract

Leachate generated in open dumpsites causes serious environmental impacts since there is a lack of

well-established leachate treatment facilities. Apotential in-situ leachate treatment aims to installan

economically feasible Permeable Reactive Barrier (PRB)system at dumpsites. The PRB in general

consists of geo-material and aggregates mixed with industrial reactive materials. The selection of

locally available geo-material with high chemical exchangeable and adsorption capacities has a key

role to develop a site-specific PRB system.The objective of this study is to characterize mineralogical

and surface charge properties for the selection of geo-material to developa site-specific PRB system in

Sri Lanka.Totally eight different soiltypes were collected considering the climate zones and soil

taxonomy in Sri Lanka: Kilinochchi,Iranamadu, Anuradhapura,Hambantotafrom the dry

zone,Bangadeniya from the intermediate zone, and Katugastota, Ukuwela, Maharagama from the wet

zone. The samples were tested for basic physical and chemical properties,ionexchange capacities, and

mineralogical compositions by X-Ray Diffraction (XRD) and X-ray fluorescence. The Pore size

distribution analysis revealed that Bangadeniya soil had the highest porosityof effective pore diameter

range, 59.3% for water absorptions. The XRD analysis found that three major constituents as

Kaolinite, Halloysite and Ca-Montmorillonitedepending on the climate zones. Integrating the

mineralogical and surface charge properties, the details on the selection of suitable geo-materials for

the site-specific PRB system will be discussed.

Keywords: Leachate, Permeable Reactive Barrier, Geometrical, Pore Size Distribution, X-Ray

Diffraction

114

SECM/13/121

MITIGATION OF SAFETY ISSUES IN TELECOMMUNICATION TOWERS

M.P.K.C. Nandapala1, R.U. Halwatura

2







Abstract

The increase in mobile phone use and newer technologies, like wireless email and web access, has created a

virtual explosion in tower construction. Even though, there are labour legislations in Sri Lanka regarding

safety issues still the state of affairs at sites are not favourable enough to safeguard the workers. There are

evidences for occurring serious accidents, injuries at an alarming level in construction sites than in other

industries during last few years. This research was carried out to understand the major safety issues in

different stages and to create the knowledge among the community on how the people and environment get

affected from the tower construction.

This research was carried out mainly by collection of information and interviews on in-house issues.

Further, a detailed survey was carried out on communication towers. It was noted that there are key issues,

which are not addressed or rather not paid enough attention from relevant authorities; such as regular

maintenance of steel structures, grounding, balancing of load, identification the role of each stakeholders,

communication lapses, lack of professionals to manage the structures after erecting, etc. Based on all the key

findings, a safety audit checklist was formulated for new and operating towers to improve the quality and

safety of the structure.

Keywords: Communication towers, safety issues, safety audit, tower management


115

SECM/13/122

HYDRAULIC STABILITY FORMULAE

FOR COASTAL STRUCTURES MADE OF GEOTEXTILE SAND CONTAINERS

D.T. Dassanayake1, H. Oumeraci

1

1Leichtweiss-Institute for Hydraulic Engineering and Water Resources, Technische Universität

Braunschweig, Germany

Telephone: 0049 531 391 3988; Fax: 0049 531 391 8217


Abstract

Instead of “hard” coastal structures made from concrete or rock boulders, the use of Geotextile Sand

Containers (GSCs), which is comparatively low cost and environmentally friendly alternative, was

applied for the first time in 1957 in the Netherlands. Few years later, many countries implemented

this innovative and unconventional method for the construction of coastal structures. Several

experimental and numerical studies have been carried out in order to investigate the applicability,

durability, and performances of GSC-structures. However, the GSC is still an emerging technology

and there are no proper design guidelines available for the design of GSC-structures for shore

protection with a sufficient scientific background.

Moreover, the long-term durability of exposed GSCs is still not fully understood and even there are

avoidable threats such as vandalism, when GSCs are installed on the shoreline. Therefore, the long

term resilience of GSCs can be enhanced by installing them as submerged or detached/offshore

structures. Once GSCs are submerged, it is expected that the durability of these elements will be

significantly increased. Nevertheless, most of the previous research studies were mainly focusing on

GSC-revetments. Hence, there is a gap in the knowledge on hydraulic stability of low crested and

submerged GSC-structures. Therefore, this research study focused on developing simplified

formulae/stability curves for the design of submerged and low-crested GSC-structures subject to

wave loads.

First, the current study evaluated the significance of important engineering properties of GSCs such

as the geotextile material, the sand fill ratio, the interface friction, etc., and their influence on the

hydraulic stability of GSC-structures. A series of experimental investigations and numerical

modelling were conducted at Leichtweiß-Institute (LWI) of Technische Universität Braunschweig,

Germany, in order to better understand the effects of aforementioned properties of GSCs on the

hydraulic stability of GSC-structures. Then, new hydraulics stability curves and formulae for the

design of GSC-structures were derived from the aforementioned experimental and numerical

investigations. This paper summarises the experimental and numerical modelling results and the new

stability formulae for GSC-structures.

Keywords: geotextile sand containers, hydraulic stability, submerged structures, low-crested

structures


116

SECM/13/123

POLYMER COATED GEOMATS AS AN ALTERNATIVE TO GEOTEXTILES IN

INTERNALLY STABILIZED WALLS

B. Jayaprakas1, K.Mahotharan

2, V.Manoj

3, L.C. Kurukulasuriya

4


Telephone: +94771921488





Telephone: +94775208013



Telephone: +94-81-2393514


Abstract

In this study, the lateral deformation characteristics of a model vertical embankment reinforced with

polymer coated coir geomats are compared with the lateral deformation characteristics of the same

model embankment reinforced with uncoated coir geomats or geotextiles. For this purpose, a vertical

embankment of height 500 mm and length 700 mm was formed by using coated coir geomats of

length 605 mm at a vertical spacing of 100 mm as reinforcement in a soil having shear strength

parameters of cʹ=5 kPa and ʹ=31° compacted to 95% of standard Proctor density. The embankment

was initially loaded at its natural moisture content up to a maximum surcharge pressure of 100 kPa

through a rigid steel plate and was then unloaded. It reloaded again up to a maximum surcharge

pressure of 250 kPa and unloaded. The embankment was then soaked over a period of 48 hours

ensuring no erosion of the soil takes place during the process and again the embankment was loaded

up to a maximum surcharge pressure of 250 kPa. During the above loading and unloading processes

the lateral deformation along the central vertical axis was measured at the mid-height of each soil

layer.

Based on the laboratory experimental model study, it can be concluded that irrespective of whether

the loading is applied under natural moisture content of the fill or soaked condition, the polymer

coated coir geomat reinforced vertical wall showed similar lateral deformation characteristics to that

of uncoated coir geomat or geotextile reinforced wall, at the same fraction of the allowable surcharge

pressure corresponding to each material. This implies that the improvement of the durability of coir

geomats by coating a waste polymer material will not affect the lateral deformation characteristics of

the coir geomat reinforced wall.

Keywords: durability, coir, lateral deformation, model test

117

SECM/13/125

STUDY ON COMPRESSIVE STRENGTH OF GEOPOLYMER MORTAR

Venumadhav.T 1, Radhakrishna

2,Ramana Reddy I.V

3, Vaishali G Ghorpade

4

1Department of Civil Engineering, Audisankara college of Engineering &

Technology,Gudur, Andhra Pradesh

Telephone:+91-9440879958


2 Department of Civil Engineering, R V College of Engineering, Bangalore - 560 059,

India

Telephone:+91-9886127398


3SVUCE , S V University Tirupathi

Telephone:+91-9849678039


4JNTUA College of Engineering, JNTU Anantapur

Telephone: +91-9440497939


Abstract

India is one of the Developing countries that needs to face the environmental pollution. Have

many ways to reduce environmental pollution that causes by production of Portland cement

and cause by the increasing of waste material. This paper studies the strength development in

geopolymer mortar using industrial by-products. Geopolymer is the term used to represent the

binders produced by polymeric reaction of alkaline liquid with silicon and aluminium as

source materials. The by-product materials considered in this study are combination of

GGBFS and Fly ash. The experimental program involves casting of geopolymer mortar cubes

and testing them at 1 day, 3 days and 7 days for compressive strength. Different parameters

considered in this study are ratio of sodium hydroxide to sodium meta silicate (1:1 &1:2 ) and

alkaline fluid to binder ratio Keeping 12-Molarity of the alkaline liquid as constant. It can be

concluded that the strength increased with an increase in the quantity of GGBFS.

Keywords: Geopolymer, Alkaline solution, cement concrete, fly ash, slag, sustainable

technology.




118

SECM/13/126

DAMAGE DETECTION IN CABLE STRUCTURES USING VIBRATION

CHARACTERISTICS

W. R. Wickramasinghe1, D. P. Thambiratnam

2, T. H.T. Chan

3

1School of Civil Engineering & Built Environment, Queensland University of Technology, Brisbane,

Australia.

Telephone: +61414437260



Australia.



Australia.


Abstract

Cable structures find many applications such as in power transmission, in anchors and especially in

bridges. They serve as major load bearing elements in suspension bridges, which are capable of

spanning long distances. All bridges, including suspension bridges, are designed to have long service

lives. However, during this long life, they become vulnerable to damage due to changes in loadings,

deterioration with age and random action such as impacts. The main cables are more vulnerable to

corrosion and fatigue, compared to the other bridge components, and consequently reduces the

serviceability and ultimate capacity of the bridge. Detecting and locating such damage at the earliest

stage is challenging in the current structural health monitoring (SHM) systems of long span

suspension bridges. Damage or deterioration of a structure alters its stiffness, mass and damping

properties which in turn modify its vibration characteristics. This phenomenon can therefore be used

to detect damage in a structure. The modal flexibility, which depends on the vibration characteristics

of a structure, has been identified as a successful damage indicator in beam and plate elements, trusses

and simple structures in reinforced concrete and steel. Successful application of the modal flexibility

phenomenon to detect and locate the damage in suspension bridge main cables has received limited

attention in recent research work. This paper, therefore examines the potential of the modal flexibility

based Damage Index (DI) for detecting and locating damage in the main cable of a suspension bridge

under four different damage scenarios. Towards this end, a numerical model of a suspension bridge

cable was developed to extract the modal parameters at both damaged and undamaged states. Damage

scenarios considered in this study with varied location and severity were simulated by changing

stiffness at particular locations of the cable model. Results confirm that the DI has the potential to

successfully detect and locate damage in suspension bridge main cables. This simple method can

therefore enable bridge engineers and managers to detect and locate damage in suspension bridges at

an early stage, minimize expensive retrofitting and prevent bridge collapse.

Keywords: Suspension bridges, Main cable, Damage detection, Structural health monitoring, Vibration

characteristics, Modal flexibility



119

SECM/13/127

CLIMATE PROOFING THE COASTAL POLDERS OF BANGLADESH

Md. Habibur Rahman1, Zahirul Haque Khan

2,Ranjit Galappatti

3

1DevConsultants Ltd, Bangladesh, Deputy Team Leader (CEIP)

Telephone: +880 1199808796


2Institute of Water Modelling, Bangladesh, Head of Coastal & Estuaries


3DHI Water Environment Health, Denmark, Team Leader (CEIP)

Telephone: +94 777773917, +91 87 4998 9954


Abstract

The coastal zone in southern Bangladesh adjoining the Bay of Bengal has a natural morphology built by the

delicate balance between the large upstream sediment inflows to the flat delta and the high tides (3-6 m

range) and extremecyclones coming in from the Bay of Bengal and very large sediment flows from

upstream. Beginning in the 1960s and continuing till today, the construction of a system of polders where

earth embankments prevent flooding of the low lying lands (1-2m above MSL) during the highest tides are

now an established feature. The ability to drain the land during low tide that occurs twice a day has made it

possible to build 139 polderswherein 1.2 million hectares of new land are now under permanent agriculture.

Some embankments are destroyed by storm surges accompanying frequent cyclones crossing over

Bangladesh. The polder system had also been affected by siltation of the river system triggered by the

massive interference with tidal volumes consequent to the prevention of tidal flooding in the delta. The

World Bank financed emergency repairs of the severe damage cause by Cyclone Sidr (2007) and Cyclone

Aila (2009)and followed this up with a longer term Coastal Embankment Improvement Programme (CEIP)

to provide protection against anticipated long term impacts of sea level rise and increased cyclone intensity

predicted in climate change projections. This paper describes the first phase of this programme.

The paper describes the use of a cyclone model in the Bay of Bengal and drainage models in individual

polders to design a new system that takes into account future storm surge heights, wave run-up, in the

design of embankment and the redesign of drainage systems to counter sea level rise as well as changes in

precipitation. The continuing subsidence of all protected lands in the coastal zone and the resulting

uncertainty with regard to theexisting standard leveling grid and the crest levels of existing

embankmentsrequired that a newcarefully devised strategy is adopted for design of both the new drainage

systems and in setting the embankment crest levels as also described in the paper.

Keywords: Storm Surge, Climate Change, Wave Run-up, Embankment Design, Land Subsidence




120

SECM/13/128

COSATAL FLOOD REMEDIAL MEASURES

PHYSICAL MODEL STUDY FOR FARES-MAATHODA ISLAND, HUVADHU ATOLL

IN MALDIVES

I.G.I.K.Kumara1, D.M.S.S.Dissanayake

2, I.L.Abeygoonasekara

3, K. Raveenthiran

4,

K.P.M.Fernando 5, S.P.Samarawickrama

6

1Lanka Hydraulic Institute Ltd, Katubedda, Moratuwa, Sri Lanka.

Telephone: +94112650409; Fax: +942650470











Telephone: +94112650567; Fax: +94112651216


Abstract

In past few decades, coastal flooding was a significant natural disaster. Storm and storm surges, high

tides, sea level rise and tsunami are the key factors for coastal flooding. Most of the low-lying coastal

lands were severely inundated by the coastal flood. Over 50 percent of the global population and 65

percent of cities with populations over five million people are in the coastal zone, and most of they

have being experiencing coastal flood. In addition to the significant number of people at risk, coastal

flooding has implications to economy of the country. The ecosystems like coastal wetland and

estuaries which posses rich bio diversity have also obliterated by this phenomenon.

Maldives is a country having topographical variation of maximum of 2 metres above mean sea level.

In May 2007 on four subsequent days, powerful swells hit many islands throughout Maldives.

According to the Department of Meteorology, Maldives, generated wave heights were 10-15 feet at

3,500 miles south west of Maldives. Huvadhu Atoll was the most severely affected of all 88 impacted

islands in 18 atolls. The maximum inundation measured was in excess of 1.5 m on the island of Fares-

Maathoda in same atoll. This paper is to propose most sustainable engineering interventions to

eliminate or to reduce the impacts from future flood events by minimizing impacts to existing

environment of the Island and adjacent Islands by using a 3D physical model. Model study has been

use to analyse capability of the different structures during extreme flood events and examine the

change of current pattern around the Island.

Keywords: Coastal flood, Swell, Inundation, 3D physical model, Current pattern












121

SECM/13/129

DEVELOPMENT OF HARBOUR LAYOUT FOR M’BORO PORT IN SENEGAL

K.P.M.Fernando1, I.G.I.K.Kumara

2, I.L.Abeygoonasekara

3, K.B.A.Silva

4, K. Raveenthiran

5,

S.Wickramaratne 6


Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470


Abstract

Harbor is a main communication and service hub of a country. The intended goals in designing and

constructing a harbor are obtaining a relatively large area of water, with adequate depth during all tidal

stages that will provide shelter for ships and providing a means by which to transfer cargo and passengers

between ships and shore locations and facilities. Port layout planning is critical in many facts, as it should be

comply with set standards as well as coastal environment of the surrounding area. Proper attention should be

made on designing the orientation, dimensioning the maneuvering area, selecting harbor depth and

providing required services while ensuring the calmness of the harbor basin and entrance channel via

modeling techniques.

Senegal is the largest producer of high quality Phosphoric Acid and Phosphates to the global market and this

involves unloading imported raw materials and loading marketable phosphate products. The current export

and import are primarily through port terminal in Dakar which has no room for expand its capacity. It was

decided to increase the import/export capacity to counteract the present and future demand of the industry.

In a view of further expansion of import and export facilities, a new marine terminal is proposed at Grande

Cote, 8km South-West of the city of Mboro, and about 15km from the acid manufacturing plant in Darou.

The design includes a jetty with two berths for ships of about 40,000 DWT, one each for bulk and liquid.

Future expansions in a period of one to two years shall be for 75,000 to 80,000 DWT. Therefore this paper

investigates the studies of port planning and layout optimization of the proposed new harbor at M‟boro,

Senegal by providing favorable conditions for attaining tranquility of the harbor basin.

Keywords: Vessel draft, Basin depth, Approach channel, Maneuvering Area, Harbour tranquility








122

SECM/13/130

OPTIMIZATION OF COASTAL FLOOD MITIGATION MEASURES USING NUMERICAL

MODELING TECHNIQUE, MALDIVES

I.L.Abeygoonasekara1, D.M.S.S.Dissanayake

2, I.G.I.Kumara

3, K. Raveenthiran

4, K.P.M. Fernando

5,

S.P.Samarawickrama6


Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470



Telephone: +94112650409; Fax: +942650470


6Department of Civil & Environmental Engineering, University of Moratuwa, Sri Lanka

Telephone: +94112650567; Fax: +94112651216


Abstract

During the four day period commencing on 15th May 2007, powerful swells hit many islands

throughout the Maldives and Huvadhu Atoll was the most severely affected among all the 18 affected

atolls with 88 islands by floods. The maximum inundation measured was in excess of 1.5 m on the

island of Fares-Maathoda in the Atoll. The island of Fares encountered intense flooding for three

consecutive days causing it to submerge entirely and nearly one third of Maathoda Island was also

flooded. No serious flooding of Fares-Maathoda has been reported since its join by the reclamation of

the passage which used to pass high wave surges between two islands in 1990s, until this event.

Numerical model study using DHI‟s MIKE software was employed to investigate the best suited flood

mitigating measure for Fares-Maathoda Island, Maldives. Effectiveness of the possible engineering

interventions or the combinations was studied to discover the most feasible solution to coastal

flooding due to extreme wave conditions. Near-shore wave modelling was required to establish the

design conditions of the coastal structures proposed. Wave calmness study was carried out to assess

the effectiveness of the offshore breakwater and revetments under extreme wave conditions.

Hydrodynamic modelling was conducted to predict the circulation patterns and establish the canal

system required under extreme conditions and was also helpful to assess the changes in circulation

patterns and other related impacts due to the proposed coastal interventions under typical wave

conditions. Results of the studies concluded continuous offshore breakwater-wide structure was the

most suitable and confirmed further by stability studies.

Keywords: Numerical model, coastal flooding, extreme wave, engineering interventions












123

SECM/13/132

STRUCTURAL HEALTH MONITORING USING GPR TECHNIQUE

A.C.M. Suhoothi1, U.L.M. Arsath

2, S. Karunanayake

3, M.I.M. Rusdhi

4,

L.W. Galagedera5, P.B.R. Dissanayake

6


Telephone: +94 778 468 522


2Department of Civil Engineering, University of Peradeniya, Srilanka



Telephone: +94 777 809895




5Department of Agric. Engineering, University of Peradeniya, Srilanka.



Telephone: +94 777 809895; Fax: +94 81-4476797


Abstract

Structural Health Monitoring (SHM) aims to give, at every moment during the life of a structure, a

diagnosis of the state of the constituent materials, of the different parts, and of the full assembly of these

parts constituting the structure as a whole. The state of the structure must remain in the domain specified in

the design, although this can be altered by normal aging due to usage, by the action of the environment,

and by accidental events. Especially, as a result of the reinforced concrete of which rebar will get

corroded the structure become older and older the diameter of the rebar would reduce, therefore flexural and

shear cracks would occur. All in all the structural health monitoring is a vital role in structural engineering..

Even though there are some published methods to assess applications of GPR technique, many of them

were developed in geological and archaeological fields. However during preliminary studies, the theory of

GPR was studied and the model was prepared in order to get the requirement of objective. Then, the model

was tested using GPR and other non-destructive tests. In addition, the actual existing footing was tested

using GPR. If there are many non-destructive tests are used in the world, this paper illustrates the accuracy

of GPR than accuracy of other non-destructive tests. In addition, it describes what are the benefits GPR has

to help in structural health monitoring.

Keywords: Structural Health monitoring, GPR, flexural and shear cracks.



124

SECM/13/134

CRITICAL ASPECTS OF WEB BASED ERP SYSTEM FOR CONTRACTORS

A.A.D.A.J. Perera1




Abstract

Organizations including contractors now accept that ERP system is a necessity to maintain

organization efficiency, competitive advantage, controls and communication. There are a large

number of ERP system today, and the facilities, the technology and the cost of these systems vary a

quite a lot. Further, many ERP systems now have offered web base access; i.e. a server based system

with remote access through a web browser. The large cost variation is mainly due to expensive

propriety systems to open source systems. Therefore, it is important to study the critical aspects of

ERP systems for contractors especially related to available facilities, fit for construction business

process, compatibility for available IT infrastructure, ease of use, fit to IT competency of employees

and critical factors for successful ERP implementations.

ERP systems evolved thorough the needs in manufacturing sector. The history of EPR development

goes back to 1970 where it first appeared as material requirement planning (MRP) and further

developed using database management systems (DBS) in 1980s and evolved to Enterprise Resource

Planning (ERP) in 1990s. As such almost all ERP systems have been design and developed for

manufacturing sector. The main business functions in an ERP are Marketing and Sales, Supply Chain

Management, Accounts and Finance and Human Resource Management. The business of functions

related Accounts and Finance, and Human Resource Management do not show variations from

manufacturing organizations to construction organization. However, many ERPs do not have correct

business processes of construction organization in the areas of Marketing and Sales (Estimating and

Tendering) and Supply Chain Management (Construction, purchasing, site management etc). An

analysis among large stock market listed construction companies who have implemented ERP have

proved that construction organizations can achieve increased profits, increased revenue and a short

payback period. An analysis for fit IT infrastructure established that many ERP systems do not fit

with IT infrastructure to connect construction sites. The available speed of connectivity is main

problem and a few ERP however meet this need very satisfactorily. An analysis of ERP system

showed that the leading system require large hardware facilities, connectivity with high bandwidth

and continuous support of vendors for maintenance. Further, the software complexities of many

ERPs do fit the IT competency level of employee and to overcome this extensive training is required

which is expensive. The successful implementation of ERP the main factors are top management

support, software complexity the fit with available IT facilities and user training.

Keywords: ERP, Enterprise Software, Project Management


125

SECM/13/135

WEB BASED WASTE WATER ASSET MANAGEMENT SYSTEMS

A. A. D. A. J. Perera1, S. Nanayakkara, P. Perera

3










Abstract

Asset management is systematic and coordinated activities and practices through which an organization

optimally and sustainably manages its and asset systems, their associated performance, risk and expenditure

over their life cycle for the purposes of achieving its organizational strategic plan. The waste water asset

system include scattered assets such sewer network pump stations, treatment plants or sea out falls, and

equipment used for operation activities. Further, these assets management and maintenance by scattered

sub organizations and planning, coordination of the work is difficult. A study were held with aim of

establishing the need of asset management system related wastewater infrastructure and feasibility of

incorporating web based systems together Google maps to incorporate the GIS aspects.

The asset management system first need hold updated asset conditions. Waste water pipe network, the

condition is established through public complains, inspection of maintenance staff and CCTV inspections.

The conditions of plant such water pumps and other related machinery are reported by staff. These

conditions are continuously changing and maintaining up to date information is one of the main needs. The

details of pipe networks are generally available in a GIS system, however it is single computer based and

not available across the organization. The integration of information requires wide range of technology and

can be expensive. Therefore, feasibility study was held for developing an asset management system using

open source technology and Google maps. The study established that using open source technology a web

based asset management system is feasible to develop together with Google maps. It was further

demonstrated that the cost of such a development is much lower the even a GIS system. The details of the

system together with sample data of a municipality are given.

Key words: Asset Management, Waste Water Systems, Infrastructure, Enterprise Systems




126

SECM/13/136

SEISMIC PERFORMANCE ASSESMENT OF REINFORCED CONCRETE FRAMED

BUILDINGS IN SRI LANKA (A CASE STUDY)

S.K.A. Gunaratne1, C.S.Lewangamage

2

1Designs, Research & Development Section, Central Engineering Consultancy Bureau, Srilanka.

Telephone: +94 714 425262; Fax: +94 112 668956


2Department of Civil Engineering, University of Moratuwa, Srilanka.

Telephone: +94 715 323239; Fax: +94 112 651216


Abstract

Sri Lanka is considered to be in an aseismic zone (zone 0) away from major plate boundaries or any

active faults. However, the first Earthquake hazard recorded on 14th April 1615 in Colombo with

about 2000 deaths and destroying 200 houses. Since then, there have been many seismic events in Sri

Lanka and neighbouring areas which are small to moderate in magnitude of which the tremorswere

felt by the people in some of the regions in Sri Lanka. Therefore, Sri Lanka has to be considered to be

situated in higher seismic zones with respect to the seismic risk for the structures.

Despite the above situation in Sri Lanka, almost all the buildings have not been designed and detailed

for earthquake resistance. Hence, it is high time to commence not only the design and detailing of the

buildings for seismic resistance but also the seismic assessment and retrofitting of the existing

important buildings. Nevertheless, detailed seismic performance assessments considering the in-situ

conditions of the buildings are new to Sri Lanka.

Therefore, as an initiative for such future assessments, this study appraise the applicability and

importance of pushover analysis for seismic assessment of a medium rise reinforced concrete framed

building having a large floor area incorporating all As-built details. Pushover analysis procedure

given in ATC 40 and FEMA 356 guidelines were used to carry out the performance assessment using

SAP 2000.

It is found from the study that the building performs at Immediate Occupancy performance level for

serviceability earthquake in seismic zone 1 (CA=0.06, CV=0.09). In addition, found that the building

can safely withstand a maximum ground motion having acceleration coefficients of CA=0.11 and

CV=0.17 performing at Immediate Occupancy performance level. Furthermore, it concludes that the

pushover procedure is applicable and realistic results can be obtained for the building considered.

Keywords: Seismic assessment, Performance based design and Non linear static Pushover analysis.



127

SECM/13/137

PROBABLE FAILURE MODES OF COASTAL STRUCTURES IN MIYAGI AND

FUKUSHIMA PREFECTURES DUE TO THE 2011 GREAT EASTERN JAPAN

EARTHQUAKE TSUNAMI

R. Jayaratne1, B. Premaratne

2, T. Mikami

3, S. Matsuba

4, M. Esteban

5, T. Shibayama

6, M. Marriott

7

1,2,7

School of Architecture, Computing & Engineering, University of East London, UK

Telephone: +44 (0)208 223 2536; Fax: +44 (0)208 223 2963

E-mail: [email protected],

[email protected],

[email protected]

3,4,6

Department of Civil & Environmental Engineering, Waseda University, Japan

Telephone/Fax: +81 (0)3 5286 8296

E-mail: [email protected],

[email protected],

[email protected]

5Graduate School of Frontier Sciences, University of Tokyo, Japan

Telephone/Fax: +81 (0)80 4026 7791


Abstract

Coastal dikes can be generally an effective way of controlling floods, wave overtopping, debris flows,

coastal erosion, landslides, and even a natural phenomenonsuch as tsunamis. They will be successful in

function, if sound construction is done primarily in terms of structural stability of seaward and leeward

slopes and toe of the structure, which can resist from the strong pressures and velocities exerted by the

overflowing water. In circumstances of an extreme event occurs in a thousand years return period like the

2011 Great Eastern Japan Earthquake Tsunami, this will be a challenging and complicated task.

Understanding of probable failure modes of coastal dikes and its classification patterns is one of the most

vital elements in order to obtain reliable evaluation of risk assessment as well as reconstruction of these

structures with better stability for future tsunamis. The authors themselves carried out two detailed field

surveys on coastal structures in Miyagi and Fukushima prefectures, relatively independently from other

researchers during the summers of 2011 and 2012, as part of a research partnership between the University

of East London and Waseda University. This paper highlights the findings from the surveys particularly the

probable failure patterns of coastal dikes and seawalls in eight cities (Soma, Yamamoto, Watari, Iwanuma,

Higashimatsushima, Ishinomaki east and west coasts, and Shichigahama). These coastal defenses were

originally designed to withstand storm surges. The noticeable primary destructive modes of dikes were1)

scour failure at leeward toe, 2) failure at crown armour, 3) scour failure at leeward slope, 4) failure at

seaward toe and armour, 5) overturning failure, and 6) parapet wall failure. Notably, the most disastrous

failure pattern among above was identified as the scour failure at leeward toe and the slope (Figure 1).

Therefore,themitigation measures should be recommended so as to reinforce the leeward toe and slope of

the defenses.

Figure 1:Coastal dike failure at Iwanuma city in Miyagi prefecture due to the 2011 Tohoku tsunami.

Keywords: Probablefailure modes, Coastal dikes, Seawalls, 2011 Great Eastern Japan Earthquake

Tsunami, 2011 Tohoku tsunami, Field surveys, Structural stability, Mitigation measures




128

SECM/13/138

EVALUATION OF THE PERFORMANCE OF UNREINFORCED MASONRY BUILDINGS

AGAINST EARTHQUAKES AND SELECTION OF SUITABLE RETROFITTING METHOD

M.M.M.Samanpriya1, V.P.Sonnadara

1, G.S.Y. De Silva


2

1Department of Civil and Environmental Engineering, Faculty of Engineering,University of Ruhuna







Abstract

Sri Lanka is a country located in the Indo-Australian tectonic plate. Since the ancient time, natural

disasters like earthquakes had not been a major concerning factor for Sri Lanka. After the first major

recorded earthquake in 1615, there was no significant earthquake that affected to the country until the

recent past. Currently, the situation has been completely changed and the interest related to

earthquakes has grown up with the series of earth tremors that were taken place in Ampara,

Monaragala and Badulla district areas, especially in 2012 to 2013. Therefore, protection of both

human and properties, especially masonry structures, against earthquakes has become an interest.

Objective of this study is to investigate the critical failure mechanism of unreinforced masonry

subjected to dynamic loadings and selection of a suitable retrofitting method to minimize the damage

to both human and masonry buildings. Brick masonry wall panels were cast and diagonal shear test

and cyclic load test were carried for two types of walls: walls without applying retrofitting technique

and the walls retrofitted with “seismic belts”. It was found that critical failure pattern of unreinforced

masonry wall panel in present of an earthquake was a propagation of cracks through mortar layer in

between bottom brick layer of wall panel and foundation, resulting to separate the wall panel from the

foundation. In this study, it was found that un-reinforced brick masonry structures can be retrofitted

by using seismic belt, allowing sufficient time for people to escape safely from their masonry

dwellings, when an earthquake occurs.

Keywords: Un-Reinforced brick masonry buildings (URM), seismic risk, retrofitted wall panels


129

SECM/13/139

DEVELOPMENT OF A BRIDGE ASSESSMENT TOOL TO IDENTIFY CURRENT

CONDITION OF REINFORCED CONCRETE AND PRE-STRESSED CONCRETE

BRIDGES

Kariyawasam K.K.G.D.D.L1, Hemapala U.B.H.U

2, De Silva Sudhira

3, De Silva Subashi

4

1Department of Civil and Environmental Engineering, Faculty of Engineering, University of Ruhuna






Abstract

Sri Lanka has many reinforced, and pre stressed concrete bridges along the coastal region of the country.

The bridges along the coastal region has high risk of initiating corrosion, compared with the bridges in

country side, due to high concentration of chloride iron and carbon dioxide in the surrounding area. The

corrosion can cause to deteriorate the bridges. As a result the bridges along the coastal region do not often

achieve their design life. Unsafe structural elements can lead for the severe disasters and it may cause even

death of people. Therefore, the bridges must be repaired, replaced or strengthened at an appropriate time.

Objective of this study is to develop a bridge assessment tool, which can be used to identify current

condition of reinforced and pre-stressed concrete bridges.

Unsafe structural elements were identified through visual inspections and assessments..The current

condition of six bridges in the coastal region from Galle to Matara was assessed by using non-destructive

tests:, rebound hammer test, resistivity test, cover meter test and ultrasonic pulse velocity test. In addition,

six bridges were visually inspected and conditions of several elements were recorded. A rating system was

applied to define a soundness score for bridges. An assessment tool to identify current condition state and to

predict required maintenance level was developed using field data and is discussed in this paper.

Keywords: Corrosion, Visual inspections, Non-destructive test

130

SECM/13/140

UTILIZATION OF BOTTOM ASH AS A CONSTRUCTION MATERIAL

Senaratna A.U.1, Weerasinghe W.P.N.

2, Subashi De Silva

3,Sudhira De Silva

4








Abstract

Utilization of bottom ash; which is a by - product of coal combustion, will be an appropriate solution

for the arising environmental problems as well as the scarcity of raw materials Although bottom ash

has the properties which suits for building constructions, still bottom ash is considered as a waste

material and is being dumped to the lands in large quantities.

Concrete paving blocks, which have multiple advantages such as fast in assembling, excellent

drainage capacity, easy handling and fast production, are increasingly used in Sri Lanka. Objective of

this study is to utilize bottom ash in production in paving blocks.

Paving blocks were manufactured using bottom ash in varying replacement levels of fine aggregates

(i.e., sands), (0%, 5%, 10%, 15% and 20% by weight) in order to determine the optimum replacement

level. Chemical composition and physical properties (i.e., density and particle size distribution) of the

bottom ash were investigated. In addition, compressive strength, splitting tensile strength, workability,

weather resistance, water absorption, and eroding of the developed blocks were investigated. It has

been found that bottom ash can effectively, be utilized in the manufacturing of paving blocks.

Keywords: Bottom ash, paving blocks, Compressive strength, splitting tensile strength weather

resistance


131

SECM/13/141

INVESTIGATION ON CHARACTERISTICS OF VIBRATION INDUCED BY

CONSTRUCTION ACTIVITIES AND ITS EFFECT ON STRUCTURAL RESPONSES

W.A.M.Wanniarachchi1, C.M. Welhena


2, G.S.Y. De Silva

2







Abstract

Vibration due to construction activities is a significant problem in urban areas. Due to the scarcity of

proper lands, people tend to use soft soil lands with deep foundations such as pile foundations, and

ground improvement techniques such as dynamic compaction. However, these activities induce

ground vibration and make damages to nearby structures. When the energy left over from a

construction activity, it transmits to the surrounding; particles in their paths are displaced by these

waves giving rise to particle velocities. However, structural response to these vibrations may vary

according to the soil type, soil-structure interaction and characteristics of the structure. The

characteristics of vibrations may also vary according to the type of construction activity. This paper

presents a study on investigating the characteristics of vibration induced by the construction activities

and effect of the vibration on structural responses.

In the current study, vibrations induced by pile driving, roller compaction and rammer compaction

were measured by using a seismograph. Characteristics of measured vibration are compared and

evaluated with respected to the guidelines given by local and international standards. Numerical

modeling was carried out with the Finite Element Modeling (FEM) using commercially available

software,SAP2000 (ver16). Structural responses of a wall panel (having a size of 3m x 5m) to

dynamic loadswere determined. A possible method to control structural responses was determined by

introducing a reinforced concrete frame to the wall. It was found that the vibration induced by pile

driving has high Peak Particle Velocity (PPV) value,around 20 mm/s,in the frequency range of 7 -

12Hz. Ground vibration (PPV) induced by roller compaction and rammer compaction is at around

2.6mm/s and2.0 mm/s, respectively. Effectiveness of reinforced concrete frame to control dynamic

responses of structures caused by the ground vibration was evaluated and discussed in this paper.

Keywords: Ground vibration, Structural damages, Guidelines, Constructions, FEM

132

SECM/13/142

INVESTIGATION ON METHODS TO IMPROVE HEALTH AND SAFETY PRACTICES IN

CONSTRUCTION SITES

Lahiru Galappaththi1,Subashi De Silva

2,Sudhira De Silva

3







Abstract

Accidents on construction sites are still a major problem in construction industry. The negligence of

safety leads to loss of productivity, accidents, health issues and several disadvantages to the

construction industry. In Sri Lanka, there are considerable numbers of accidents occur in construction

sites. With the rapid development of the country, there are many infrastructure development projects

proceeding. As a result, a considerable number of people are being employed in construction sites.

Therefore, frequency of occurring accidents is increasing. Investigation on an effective method to

improve the safety and health practices and reduce the occurrence of fatal accidents and non-fatal

accidents in construction field in Sri Lanka is an urgent need. Objective of this study is to identify the

most influencing factors on the construction accidents. In addition, factors affecting safety

performances are identified and a method to improve the health and safety practices is proposed by

evaluating safety performances in construction sites.

A structured questionnaire survey form was developed for workers and management. Site visits were

made and construction workers were interviewed individually during their working time. Survey was

conducted during the time interval between 9.00a.m to 12.00noon. Workers assessed the factors

affecting safety performances and accidents in five point scale. Based on the identified most

contributory factors affecting the accidents and safety performances, methods to improve safety and

health practices were identified as “conducting safety training on Personal Protective Equipment

(PPE)”, “displaying safety and health boards in picture format” and “providing sufficient PPE to the

site”.

Keywords: Site safety, Health practices, Construction site


133

SECM/13/143

STATE-OF-THE-ART: TRACK DEGRADATION AT BRIDGE TRANSITIONS

C.Gallage1, B. Dareeju

2, M. Dhanasekar

3

1School of Earth, Environmental and Biological Sciences, Science and Engineering Faculty,

Queensland University of Technology, Australia

Telephone: +61 7 3138 1034


2School of Earth, Environmental and Biological Sciences, Science and Engineering Faculty,


Telephone: +61452521250


3School of Civil Engineering and the Built Environment, Science and Engineering Faculty,


Telephone: +61 7 3138 6666


Abstract

Transition zones between bridge decks and rail tracks suffer early failure due to poor interaction

between the rail vehicles and sudden changes to the stiffness; this has been an ongoing problem to the

rail industry, yet still no systematic studies appear to have been taken to maintain a gradually

smoothening transmission of forces between the bridge and its approach, which leads to passenger

discomfort and early damage to infrastructure and vehicle components. Differential settlement

between the bridge deck and rail track in the transition zone is the fundamental issue which negatively

impacts the rail industry which resorts to speed reduction, and frequent maintenance cycles.

Identification of origins of the track degradation with correlations of their mechanical and physical

characteristics is imperative to design any mitigation method, contributing for reducing track

degradation rate at the bridge transition zone. Unfortunately this issue is still not well understood,

after conducting a numbers of reviews to evaluate the key causes, and introducing a wide range of

mitigation techniques.

A comprehensive analysis of the available literature has been carried out to develop either a novel

design framework or a mitigation technique for the bridge transition zone. This paper addressed three

critical questions: (1) what are the causes of bridge transition track degradation?; (2) what are the

available mitigation techniques in reducing the track degradation rate?; (3) what are the factors

affecting on the poor performance of the existing mitigation techniques?. It is emphasised that in the

absence of soil-water response, dynamic loading response, behaviour of geotechnical characteristics

under long-term conditions critically influence on the failures of existing mitigation techniques. This

paper will highlight the requirement of the evaluation of the existing design frameworks to clarify

how each design framework addresses the origins of the track degradation at the bridge transition

zone.

Keywords: Bridge Transition Zone, Differential Settlement, Geotechnical Characteristics, Soil-water

response





134

SECM/13/144

BUCKLING STRENGTH ESTIMATION OF CORRODED STEEL PLATES WITH

IRREGULAR SURFACE

P. Chun1, M. Ohga

2, T. Yokogawa

3, Lusman

3, J.M.R.S. Appuhamy

4, S. Furukawa

3, P.B.R.

Dissanayake5

1Department of Civil & Environmental Engineering, Ehime University, Japan.

Telephone: +81 89 927 9822; Fax: +81 89 927 9840



Telephone: +81 89 927 9816; Fax: +81 89 927 9840



Telephone: +81 89 927 9840; Fax: +81 89 927 9840

4Faculty of Engineering, University of Ruhuna, Hapugala, Galle, Sri Lanka.

Telephone: +94 91 2245765(Ext: 4201); Fax: +94 91 2245762



Telephone: +94 777 809895; Fax: +94 81 4476797


Abstract

The deterioration of materials in many old steel bridges due to environmental exposure has become a

serious problem in recent years not only in Japan but also all over the world. Therefore, the purpose

of this research is to evaluate the residual strength capacity of corroded steel plates which are seen in

steel structures under compression in order to keep them throughout in service until it is necessary to

rebuild or retrofit them at an appropriate time. Corroded plates with irregular surfaces were examined

by experimental analysis, which will help to decide action plans in the future. This paper presents an

analysis of the behaviors of corroded plates where representative thickness parameters, i.e. the

minimum value of average thickness, are considered carefully. Buckling test results of actual

corroded plates reveal that thickness reduction, surface irregularity, and amount of eccentricity

decreased the load-bearing capacity. Furthermore, a numerical analysis has been conducted using the

commercial finite element package Abaqus to understand the buckling behavior of corroded steel

plates after the validity of the FEM model is confirmed.

Keywords: Corrosion, Effective thickness, Buckling strength, Finite element analysis





135

SECM/13/145

A PARAMETRIC STUDY ON FACTORS AFFECTING VIBRATION CHARACTERISTIC

OF SKEWED BRIDGES BY FINITE ELEMENT MODELING

P. Chun1, A. Aono

2, K. Ohkubo

2, N.N.K. Cindy

3, M. Ohga

4, S. Mori

5


Telephone: +81 89 927 9822; Fax: +81 89 927 9840



Telephone: +81 89 927 9840; Fax: +81 89 927 9840

3Department of Civil Engineering, Gadjah Mada University, Republic of Indonesia.


Telephone: +81 89 927 9816; Fax: +81 89 927 9840



Telephone: +81 89 927 9818


Abstract

This manuscript conducts a parametric study to understand the effect of degree and location of

damage on natural frequencies of skewed bridges. This research topic has been the subject of

considerable investigation over the past several decades due to the increasing number of ageing

bridges. Many works in the literature on this topic give excellent results or have raised interesting

matters for consideration; however, to our knowledge the effect of damage and dimensions on natural

frequencies has not been investigated in detail. In order to provide new knowledge, this research

attempts to clarify how far changes in damage degree and location affect the natural frequencies of

several frequency modes by finite element analysis.

We have developed a finite element model for the parametric study by using the commercial finite

element package Abaqus/standard. The finite element model was validated by the measurement

results of an actual concrete bridge in Japan so that the finite element analysis can be reliably used to

understand the behavior of a large number of generic bridges. The result of the parametric study is

expected to improve the structural health monitoring process of bridges, which in turn will improve

the safety of bridges.

Keywords: Health monitoring, Bridge engineering, Frequency analysis, Finite element analysis



136

SECM/13/146

USE OF SCRAP TYRES IN PLAIN CEMENT CONCRETE

Mukul Chandra Bora

Dibrugarh University Institute of Engineering and Technology,

Dibrugarh University, Pin: 786004, Assam, India

Tele-fax: +913732370774, Mobile: +919435533164


Abstract

India is a fast developing country. The increase in population and their living standard force to

increase in the transportation sector for carriage of passengers and goods. Transportation sector is

increasing very fast. The increase growth of transportation sector increases the number of vehicles

ranging from small vehicles for private use to heavy vehicles like trucks, buses etc for carriage of

passengers and goods. All the road transportation means uses tyres on their wheels and the tyres

become unserviceable after a number of repetitions and hence get wear and tear. These used tyres are

generally called as scrap tyres. Scrap tyres are generally dumped or burnt as fuel before few years

back and both the process make environmental hazard. To mitigate the potential environmental hazard

arises out of scrap tyres some alternative ideas have to be found out as it cannot be recycled to be used

in fresh tyres. Only the civil engineering structures can accommodate these scrap tyres and may be

used either in landfill engineering or earth reinforcement or in concrete. The potential use of scrap

tyres as a whole in landfill engineering has been found to be used in countries like UK and USA but

the use in concrete is in very nascent state. In recent decades, worldwide growth of automobile

industry and increasing use of car as the main means of transport have tremendously boosted tyre

production. In the early 1990s, extensive research projects were carried out on how to use used tyres

in different applications. Scrap tyre is composed of ingredients that are nondegradable in nature at

ambient conditions. They usually produce environmental mal-effects. One of the methods for

utilisation of these materials is their use in concrete and other building products.

In this paper the scrap automobiles tyre chips were used in concrete in place of stone aggregate in the

form of partial replacement of aggregate starting from 5% to 30 %. Concrete cubes were casted in the

laboratory and their compressive strength was calculated. The results are very encouraging and it is

found that upto the 20% replacement of the aggregate with tyre chips does not shows any substantial

decrease in compressive strength of concrete. As the weight of the rubberized concrete is less than the

normal concrete and hence it may be used as a lightweight fill for the regions of high seismicity as it

will reduce the weight of the superimposed load. The trend in strength gain for this ruberised concrete

is observed as the same as that of normal concrete.

Keywords: Transportation, automobile tyre, scrap, type chips, compressive strength

137

SECM/13/147

SENSITIVITY ANALYSIS OF PURELY EROSIONAL STEP SHAPE BED FORMS

OBSERVED IN RIVER ENVIRONMENT THROUGH LABORATORIAL RESEARCH

ATTEMPT

S. Nithiyananth1, K. Thivaharan

2, K Thusitha

3,D.D Dias

4


Telephone: +94 717 421 427



Telephone: +94 772 784 858



Telephone: +94 777 102 375



Telephone: +94812393575 / +94718721872


Abstract

Alteration of existing river beds due to the accumulation of sediments in an ordered analogy, causes

ecological and economical drawbacks. One of such peculiar bed forms observed in sub aerial environments

are cyclic steps.Cyclic steps constitute a characteristic bedform of Froude-supercritical shallow flow over an

erodible bed. They are long-wave features that are bounded by hydraulic jumps and migrate upstream. They

can be seen in alluvial streams, stream in cohesive sediment, bedrock streams, and on the seafloor in

response to turbidity currents.

Cyclic steps are one of few bed forms can successfully regenerated in a laboratory environment hence many

dimensions can be explored in relation with its formation and propagation. This paper is targeted at

obtaining the threshold condition for the formation of step shape bed forms under purely erosional set up at

a sub-aerial environment. Sensitivity of bed slope, flow rate and the bed material were tested and thereby

investigated the conditions to be satisfied for emerging these bed forms. This study was shed a light to

understand the threshold condition with respect to a certain parameter for the formation of cyclic steps, once

other conditions are controlled. Emerged resultswere verifiedwith previous research outcomes.

Keywords: Cyclic steps, sub aerial environment, formation analogy, threshold conditions


138

SECM/13/148

BEHAVIOUR OF ADVANCED REINFORCEMENT PATTERN IN EXTERIOR

REINFORCED CONCRETE BEAM-COLUMN JOINT

S.M Kulkarni1, Y. D. Patil

2

1Department of Civil Engineering, Parul Institute of Engg& Technology, Vadodara, India

Telephone: +91 989 8879519


2Department of Applied Mechanics, SardarVallabhbhai Patel National Institute of Technology, Surat,

India

Telephone: +91 999 8846518


Abstract

Current design philosophy permits moment-resisting frames subjected to seismic loading, apart from a few

exceptions, to be induced into the inelastic range where the forces that develop in parts of the structure will

exceed their design values. In this phase of inelastic intensity, the beam-column joints are obliged to resist

high horizontal and vertical shear stresses coming from the adjacent beams and columns. This occurs during

a large number of inelastic cycles, while the joints need to dissipate large energy.

Reinforced concrete beam-column joints are critical regions in reinforced concrete frames subjected to

severe seismic attack. Beam moment reversals can produce high shear forces and bond breakdown into the

joint resulting in cracking of the joint. The most important factors affecting the shear capacity of exterior RC

beam-column joints are: the concrete compressive strength, the joint aspect ratio of the joints and number of

lateral ties inside the joint. Advanced Reinforcement Pattern (ARP crossed inclined bars) is a feasible

solution for increasing the shear capacity of the cyclically loaded exterior beam-column joints. The presence

of inclined bars introduces an additional mechanism for shear transfer.

External beam-column joints with crossed inclined reinforcement (ARP) modeled in Ansys Workbench

showed high strength, and no appreciable deterioration even after reaching the maximum capacity.

Hysteresis loops are observed, with more energy dissipation capacity and it varies from 45 % to 65 % in

ARP-2 pattern, which makes the joint relatively more ductile. The load resisting capacity is increased by

1.43 times the yield strength as compared to that of seismic joint (IS: 13920-1993). The pattern shifts the

flexural hinges away from the joint thus failure occurs at the end of the beam near the column, absorbing

more energy. It increases the joint shear capacity of external RC beam-column joint by 18%.

Keywords: Critical Regions, Advanced Reinforcement Pattern, cyclically loaded, Joint shear


139

SECM/13/149

EFFECTIVE USE OF SINGLE AND DOUBLE SHELF IN CANTILEVER RETAINING

WALL

J. P. Patankar1, A. C. Chougule

2

1Applied Mechanics Department,Walchand College of Engineering, Sangli, Maharashtra, India

Telephone: +91-9850550677; Fax: +91-233-2300831


2Applied Mechanics Department,Walchand College of Engineering, Sangli, Maharashtra, India

Telephone: +91-8149303673; Fax: +91-233-2300831


Abstract

A reinforced concrete cantilever retaining wall is used in various fields of engineering such as roads, dams,

tunnels, mines etc which is designed to retain material as well as to sustain the lateral pressure due to the

material. Reinforced concrete cantilever retaining wall is always economical as compared to counterforted

wall upto certain height. The major advantages of cantilever retaining wall over counterfort retaining wall

are due to 1) saving of material 2) light structure 3) speed of construction and 4) the ease with which it can

be constructed. For greater height also, this cantilever retaining wall can be effectively used if shelves are

provided in the stem. If the shelves are extended up to rupture surface, the effective lateral earth pressure on

the wall decreases considerably (which is advantageous for stability of the wall) as compared to cantilever

retaining wall without shelf. In this paper analysis and design of reinforced concrete cantilever retaining

wall “with single and double shelf” and also “without shelf” is done. Best location of shelf for “single shelf

retaining wall”at 7/12 of stemheight from top and best locationsof two shelvesfor “double shelf retaining

wall”at 4/12 of stemheight and 7/12 of stemheight from top for the economical design of wall are foundout,

which will be of great practical use.

Keywords: retaining wall,Effective lateral earth pressure, rupture surface, double shelf, best location


140

SECM/13/150

EFFECT OF COAL BOTTOM ASH AS SAND REPLACEMENT ON PROPERTIES OF

CONCRETE WITH VARIATION IN CEMENT BY WEIGHT OF BOTTOM ASH

1M.P Kadam,

2Y.D. Patil ,

3H. S. Patil

1Applied Mechanics Department,S V National Institute Technology Ichchhanath, Surat-395007

E mail: [email protected]





Abstract

In this paper the properties of concrete are studied by using sieved bottom ash as a sand replacement.

The bottom ash was taken from Eklary thermal power plant Nashik. The natural sand and coarse

aggregates are taken from local source. In this paper a fixed percentage of bottom ash (70%) and

natural sand (30%) was taken. This percentage was used in a concrete of grade M-35. In this paper

70% sieved bottom ash and 30 % natural sand was taken with variation in cement by the weight of

sieved bottom ash which was used in the mix. In this paper slump was kept constant around 100 ± 10

mm with fixed water cement ratio. To achieve required slump the BV plasticizer was used as directed

by manufacture. The cement was increased by 5%, 10%, 15%, 20%, 25%, 30% weight of sieved

bottom ash used in the mix. The harden properties of concrete are studied like compressive strength,

split tensile strength, flexural strength, water permeability , moduluous of elasticity and density of

concrete at 7, 28, 56 112 days. These results are compared with controlled concrete and percentage

variations in strength are tabulated. It was found that cement increased by 20% weight of sieved

bottom ash in concrete then results are approximately nearer to the controlled concrete.

Keywords: Sieved bottom ash, compressive strength, split tensile strength, flexural strength, water

permeability.



141

SECM/13/151

SOLAR LIGHTING FOR A TRIBAL SCHOOL AT WADA DISTRICT OF MAHARASHTRA

Sudhakar Joshi

Engineers without Borders, Mumbai Chapter

101/102, Kensington SEZ, Hiranandani Business Park, Powai, Mumbai -400076, India


Abstract

EWB Mumbai has undertaken Project tribe stars as their flagship project for year 2012 and 2013. The

objective is to provide improved sanitation facilities, solar power and awareness campaign for

health/safety for the three (3) schools at Wada district of Maharashtra. These boarding schools

accommodate around 500 students each from Tribal area of rural Maharashtra to provide primary,

secondary education to children of underprivileged Tribal communities.

EWB, Mumbai assessed the need for provision of solar power for the school in consultation with

school authorities. The major problem is irregularity/non availability of electricity board‟s power

supply and voltage fluctuations.

Hence, there was severe shortage of adequate and quality lighting to the students for their study and

access around the campus during evening hours.

Following facilities were provided under solar project to one of these schools-

1) The system consists of suitable Solar Photovoltaic Panel, Battery, Controller and LED lights.

2) Solar powered LED lights in each classroom sufficient for study purpose.

3) Solar powered street lights in the open area/playground. These lights are mounted on

individual 15 ft high GI pole with its own solar panel, battery and LED light.

4) Two voltage stabilizers at the input of electricity grid power supply.

The benefits of solar system provided are as below:

1) Saving in electricity bills.

2) Economical because of efficient and long lasting LEDs.

3) Simple and robust.

4) Solar panels guaranteed for 10 years and batteries for 5 years.

5) Maintenance cost is absolutely negligible.

6) Voltage stabilizers will enhance the life of existing light fixtures and hence saves cost.

Keywords: Solar, LED, EWB,Wada, Maharashtra


142

SECM/13/152

STRUCTURE AND PROPERTIES OF LITHIUM TRANSITION METAL OXIDE

MATERIALS FOR ELECTRODE APPLICATIONS IN ELECTROCHEMICAL ENERGY

CONVERSION DEVICES

Athula Wijayasinghe1,2

, Pushpaka Samarasingha1,3

1Nanotechnology and Physics of Materials Project, Institute of Fundamental Studies, Hantana Road,

Kandy, Sri Lanka

Telephone: +94812232002; Fax: +94812232131


2Department of Materials Science and Engineering, KTH (Royal Institute of Technology),

Stockholm, Sweden

Telephone: +4687909134; Fax: +468207681


3 Department of Chemistry, Center for Materials Science and Nano Technology, Oslo University,

Oslo, Norway

Telephone: +4722858637; Fax: +4722855441


Abstract

In selecting for the electrochemical energy conversion applications such as for fuel cells and batteries, a

candidate electrode material must possess adequate structural and electrical property. This work is based on

developing a range of lithium transitions metal oxides, Li(NixCo(1-x-y)My)O2 (M= Fe, Mn, Zn, Cu .. etc.), for

the electrode system in the Molten Carbonate Fuel Cell (MCFC) and the rechargeable Lithium Ion Battery

(LIB).

The investigation was carried out by synthesizing these novel candidates using advanced but low-cost wet-

chemical processing techniques such as Pechini method and Glycine Nitrate Combustion (GNC) method,

which can even form nano scale fine powder particles. The prepared powders were subjected to phase

analysis by X-ray diffraction, electrical conductivity by the d.c. four probe technique and the particle

morphology by Scanning Electron Microscopy. Electrode structures were fabricated via tape casting and

their electrical conductivity was determined by the van der Pauw technique. Electrochemical testing was

performed in laboratory cells under the ambient conditions.

The outcome of this study reveals the ability of synthesizing homogeneous ultra fine lithium transitions

metal oxide electrode materials using Pechini and GNC techniques, with appropriate structural,

morphological and electrical properties for MCFC and LIB. Specially, the performance of

Li(Ni0.6Co0.2Fe0.2)O2 electrode was comparable to that projected for a commercial MCFC (cathode

polarization and ohmic drop of 62 and 46 mV, respectively). While Li(Ni0.33Co0.33Mn0.33)O2 showed of 180

mAh/g discharge capacity, which is significantly better than that (125 mAh/g) of the state of the art LiCoO2

cathode of LIB.

Keywords: Structure and properties of materials, Electrochemical energy conversion, Molten Carbonate

Fuel Cell (MCFC), Lithium Ion Battery (LIB), Lithium transition metal oxides



http://kandy.ifs.ac.lk/cgi-bin/openwebmail/openwebmail-send.pl?sessionid=athula*kandy.ifs.ac.lk-session-0.252978351506503&folder=INBOX&page=1&sort=date&keyword=&searchtype=subject&action=composemessage&message_id=%3C1375261942.17188.YahooMailNeo%40web142301.mail.bf1.yahoo.com%3E&compose_caller=read&[email protected]

143

SECM/13/153

BEHAVIOUR OF COMPOSITE SLAB UNDER STATIC LOADING

Sharda P. Siddh1, Y. D. Patil

2, H. S. Patil

3

1Applied Mechanics Department, SVNIT, India

Telephone: +919033198736



Telephone: +919998846518



Telephone: +919825450884


Abstract

Composite slab consisting of profiled steel sheeting and concrete are widely used in buildings nowadays.

The use of steel deck in combination with concrete results in an optimum solution bringing with it great

advantages such as no form work, quick installation, and reduced dimensions and weight to construction of

building floors. Essentially behavior of composite slabs is governed by the horizontal shear bond at the

interface of the steel deck and the concrete. The profile steel deck serves as tension reinforcement.

Composite flooring system is essentially consisted of one-way spanning structural components. The slab

spans between the secondary floor beams, whereas these secondary beams span transversely between the

primary beams.

In this paper, FE modeling of composite slab with considering different parameters like thickness of profiled

steel sheet and number of intermediate stiffeners has been carried out by using ANSYS Workbench-14

software. Analysis was carried out to know the overall and load-deflection behaviour of the composite slab.

It has been observed that as thickness of sheet increases, deflection decreases for the constant load.

Furthermore, the analysis shows that the intermediate stiffeners play major role to reduce the deflection.

Keywords: Composite slab, profile sheet, FE modeling, shear bond, intermediate stiffeners.





144

SECM/13/155

SUSTAINABILITY THOUGH STRUCTURAL DESIGN

Vinda Dravid1

1Sterling Engineering Consultancy Services Pvt. Ltd., Mumbai, India

Telephone: + 91 9769 439 930


Abstract

Sustainability has long since been under the purview of Architects and MEP consultants. The role of

Structural Engineers in the concept of sustainability and green buildings has not received focused

attention. However, structural design is one of the most important aspects of a building that directly

impacts the environment. Through smart design techniques, innovative schemes, optimum utilization

of materials, use of supplementary systems, correct interpretation of software output, flexible

planning, design for longevity, a structural engineer can directly reduce consumption of natural

resources and indirectly conserve energy.

In order to achieve this, a structural engineer can implement techniques that enhance stiffness and

strength while reducing material consumption. These methods allow a direct computation of energy

and material savings which can be linked to carbon emissions or embodied carbon content. These

practices may have been followed earlier for financial benefit but may now be viewed from the

perspective of green building design.

This paper compiles techniques whichcan be acknowledged as sustainable practices and other ideas

that may routinely be used in future by structural consultants. Emphasis has been given on the designs

that can be implemented conveniently with low energy consuming construction methods.

Keywords: Structural Design, reduction in consumption,sustainability.


145

SECM/13/156

EFFICIENT MAINTENANCE MANAGEMENT STRATEGY FOR

AGED STEEL BRIDGE STRUCTURES

J.M.R.S. Appuhamy1, P.D.C. Perera

2, S.N. Malkanthi

3, M. Ohga

4, P. Chun

4,P.B.R. Dissanayake

5


Telephone: +94-91-2245765(Ext: 4201); Fax: +94-91-2245762



Telephone: +94-91-2245765; Fax: +94-91-2245762



Telephone: +94-91-2245765(Ext: 4000); Fax: +94-91-2245762


4Department of Civil & Environmental Engineering, Ehime University, Japan

Telephone: +81-89-9279816; Fax: +81-89-9279816

E-mail: [email protected],[email protected]


Telephone: +94-777-809895; Fax: +94-81-4476797


Abstract

Deterioration of steel bridge infrastructures constitutes a major worldwide problem in transportation

engineering and maintenance management industry. Corrosion becomes one of the most important causes

of deterioration of steel girder bridges which reduce their load carrying capacities and eventually leads to

catastrophic collapses. Therefore, regular and detailed inspections are deemed necessary to assess the

present condition of the infrastructure and determine maintenance requirements to assure their safety. But

this will be an exigent task for bridge maintenance engineers to attend detailed condition monitoring

programs on regular basis for each and every steel bridge, with the increase of number of aged steel bridge

infrastructures. Therefore, this paper proposes an efficient maintenance management strategy for steel

bridge infrastructures corroding for decades, developed by using the results of experimental and numerical

analyses of corroded bridge members obtained from a steel girder used for about hundred years with

severe corrosion. Furthermore, the proposed system is able to provide a reasonable basis for decision

making of bridge repairing and reconstruction which are generally decided by personal experience or

custom.

Keywords: Corrosion, Experimental analysis, Maintenance management strategy, Numerical analysis,

Remaining strength



146

SECM/13/157

3D TRANSIENT ANALYSIS OF THE SOIL-STRUCTURE INTERACTION THROUGH AN

ITERATIVE COUPLING TECHNIQUE

J. Labaki1,D. A. Damasceno

2,E. Mesquita

3

1Department of Computer Mechanics, School of Mech Engineering, University of Campinas, Brazil

Telephone: +55 (19) 3521-3395



Telephone: +55 (19) 3521-3395



Telephone: +55 (19) 3521-3203


Abstract

This paper describes a methodology to analyse the transient response of structures interacting with

underlying soil profiles by means of an iterative coupling scheme. The structures are modelled by the

classical Finite Element Method and the classical Newmark method is applied to integrate the

governing equations of motion in the time domain. The considered soils are viscoelastic and present

distinct geomechanical profiles. The transient soil response to a general dynamic loading is obtained

by convoluting the soil transient impulse response with the applied external load.

The present method of analysis consists in subdividing the coupled soil-foundation problem in two

subsystems. The first subsystem comprises the elastic structure. The second subsystem is the soil. In

the first step Green‟s functions in the frequency domain are obtained for the considered

geomechanical profiles. A robust integration scheme allows the frequency domain solution to be

accurately determined for very high frequencies. These frequency domain solutions may be used in

conjunction with the Fast Fourier Transform to yield transient soil impulse response with very small

time steps.

The proposed iterative solution technique couples the transient response of the structure, determined

by the Newmark integration method, with the soil transient response, obtained in terms of a time

convolution integral. For each time step the iterative procedure seeks for a solution that fulfils

displacement continuity and force equilibrium conditions at the soil-foundation interface. The

iterative technique takes advantage in the fact that every substructure, i.e. soil and structure, may be

solved by the best suitable method for each domain.

The proposed strategy is used to analyse representative problems of columns under axial loads, beams

with lateral loads and frames that are clamped in the soil in two or more different points. The method

enables investigating the effect of different soil profiles and properties on the dynamic response of

internally or externally excited structures.

Keywords: Soil-structure interaction, coupled systems, iterative solution technique

147

SECM/13/159

STRUCTURAL SYSTEM FOR LOW COST HOUSING SCHEME

Alka K. Jain

Black & Veatch Consulting Pvt. Ltd. Mumbai, India


Abstract

Accessibility to housing for low to moderate income groups in India has been experiencing a severe

decline since 2008. On the supply side, the public sector has been reducing its commitment to the

direct provision of public housing. The Government can promote housing development to achieve

value for money in expenditure on affordable housing in any type of terrain.

Low cost housing is effectively deals with budget and the cost of the construction without sacrificing

the strength, performance and life of the structure. The low housing schemes can be done by selecting

more efficient material or by an improved design.

For any type of building the foundation, walls, doors and windows, floors and roofs are the most

important components, which can be analyzed individually based on the needs thus, improving the

speed of construction and reducing the construction cost. The major current methods of construction

systems considered here are namely prefabricated structural frames, panel walls, prefabricated roofing

are considered.

The basic idea of this paper is to design structure having properties like environment friendly, light

weight, easy for maintenance, and ease in construction and offer stability in wind and seismic loading.

This can be useful for mass housing and offer speedy construction.

It is primarily frame structure built by using steel hollow section and GI light weight section Roof

consist of GI profile sheet. Best suitable option were work out by using various combination of sizes,

shape and position of structural element.

Instead of brick or block work, A system of wall panels made from fiber cement sheets, EPS

(Geofoam) and mortar was proposed. These wall panels acting as non structural members.

Various types of mortars based on costing was proposed like cement mortar, lime mortar and special

mortar made in combination of sand, cement and Bentonite(for thermal insulation).

Foundation system is proposed as slab on grade with wire mesh 300 mm above NGL for normal

terrain, In submerged areas floating foundation system was proposed by using Geofoam.

Keywords: Sustainable development, affordable housing, Environmental friendly, speedy

construction, easy for maintenance


148

SECM/13/160

SEISMIC VIBRATION CONTROL OF ASYMMETRICAL BUILDING

INSTALLED WITH LINEAR VISCOUS AND NON-LINEAR VISCOUS

DAMPERS

Suhasini N. Madhekar1,2DhanashreeR.Tulankar

1Department of Civil Engineering, College of Engineering Pune, Pune-411005, India


2Department of Civil Engineering, College of Engineering Pune, Pune-411005, India


Abstract

The dynamic response of the eight story asymmetric building with linear viscous dampers (LVD)and

non-linear viscous dampers (NLVD) is investigated under two prescribed earthquake groundmotions.

The eight story building is modeled as a shear building with lateral and torsionaldegrees-of-freedom

at each floor. The results of the asymmetric building installed with LVD andNLVD are compared

with the corresponding uncontrolled response. Also the controlled responseof asymmetric building is

compared with symmetric building to study the effects of torsionalcoupling. The performance of the

building is studied by solving the governing equations ofmotion using state space method. The Indian

ground motions used are of Koyna (1967) and Bhuj (2001)earthquake. In addition, a parametric study

is also carried out to critically examine the behaviourof the asymmetrical building. The important

parameters considered are eccentricity ratio andfundamental time period. The response of the

asymmetric building with LVD and NLVD isanalyzed and compared with the corresponding

uncontrolled case. From the above investigationit is concluded that compared to LVD, NLVD are

quite effective in reducing peak responsequantities of the asymmetric building. The NLVD can be

implemented in practice for upgradingthe seismic performance of asymmetric buildings.

Keywords: Asymmetrical building, seismic response, linear viscous dampers, non-linear viscous

dampers, torsional coupling



149

SECM/13/163

EARLY AGE BOND STRENGTH OF REINFORCING BARS IN HIGH STRENGTH

CONCRETE

S.H. Chowdhury1

1Griffith School of Engineering, Griffith University, Gold Coast Campus, Queensland, Australia.

Telephone:61-7-55528662; Fax: 61-7-55528065


Abstract

With increasingly short deadlines in the construction industry, early strength of concrete is becoming more

and more important as it allows construction to continue at an earlier date. Bond strength is an important

property in concrete construction as it determines the amount of tensile stress a concrete member is able to

withstand safely.

Research has been carried out on bond strength of normal strength concrete with normal reinforcing bars but

not a lot has been done on bonding capacity of reinforcing bars in high strength concrete especially at early

age. In this experimental investigation an attempt has been made to determine the bond strength properties

of normal reinforcing steel in high-strength concrete at early age. Test cylinders were cast with reinforcing

bars inserted in them from two different strengths of concrete – one of normal strength of 30 MPa and the

other of high strength of 60 MPa. The cylinders were subjected to pull-out tests for bond failure at early ages

of 4, 7 and 14 days. The obtained results were compared with those predicted using published bond strength

formulas. Initial findings indicate a consistent increase in bond strength with increase in concrete strength

and relative brittleness of higher strength concrete.

Keywords: Early age bond strength, Pull-out test, High strength concrete, Bond strength prediction

formula


150

SECM/13/164

EFFECT OF SUPPLEMENTARY CEMENTING MATERIAL (SCM) SUCH AS NANO

SILICA, MICRO SILICA, FLY ASH AND BOTTOM ASH ON PROPERTIES OF

CONCRETE

Thushara Priyadarshana1, Madhuwanthi Rupasinghe4, Gamini Chandrasena2, Priyan

Mendis4, Ranjith Dissanayake3

1Holcim (Lanka) Limited


2Innovation & Application Center, Holcim (Lanka) Limited, Colombo 14, Sri Lanka


3Dept. of Civil Engineering, University of Peradeniya, Peradeniya 20400, Sri Lanka


4Department of Infrastructure Engineering, The University of Melbourne, Australia,


Abstract

In this study, supplementary cementing material (SCM) such as nano silica, micro silica, fly ash and

bottom ash have been evaluated for optimal level of replacement as blending material in cement. The

physical and chemical properties of above materials were first analyzed. Then properties of concrete of

fixed mix design (G35 concrete) were investigated. Mainly this study focused on compressive strength

of concrete with different mixes at different age of concrete.

Test results obtained in this study indicate that up to 5% nano silica, 10% of micro silica, 20-30% of fly

ash and 10% of bottom ash could be advantageously blended with cement without adversely affecting

the strength. However, optimum levels of these materials are 1-3% of nano silica, 3-8% of micro silica,

10% of fly ash and 5% of bottom ash when we consider the strength of concrete.

Keywords: supplementary cementing material (SCM), fly ash, nano silica, micro silica,

bottom ash




151

SECM/13/165

BENEFITS OF BLENDED CEMENTS IN CONCRETE

Thushara Priyadarshana1, Gamini Chandrasena

2, Ranjith Dissanayake

3

1Holcim (Lanka) Limited, Colombo 14, Sri Lanka


2Innovations & Application Center, Holcim (Lanka) Limited, Colombo 14, Sri Lanka


3Department Of Civil Engineering, University Of Peradeniya,Peradeniya,Sri Lanka

3Email:[email protected]

Abstract

Concrete is the most widely used material in the world for construction and cement is the most

important component in it. Even though EN code recommend 27 types of cements and SLS recomens

3 types of cements for concrete applications, the benefits of each cment types are not well known. In

this study, locally available blended cement types Ordinary Portland Cement, Hydraulic Blended

Cements (fly ash cement) and Portland limestone cements (PLC) produced under SLS 107, SLS 1247

and SLS 1253 are evaluated their properties in concrete.

The physical and chemical properties of above cement types were first analyzed. The properties of

concrete in different mixes to represent grade20, grade 25, grade30, grade40 include compressive

strength, setting times, workability and water permeability were observed. Based on results, benefit of

blended cements over OPC cements are estimated.

Keywords: Blended cement, durable concrete, limestone cement, fly ash ecement




152

SECM/13/166

SEDIMENT CONTAINMENT THROUGH EFFECTIVE SILT-SCREEN DESIGN

Thu-Trang Vu1, Soon-Keat Tan

2

1DHI-NTU Centre, Nanyang Environment and Water Research Institute,

Nanyang Technological University, Singapore.

Tel: +65 6790 6618. Fax: +65 6790 6620


2Maritime Research Centre, School of Civil and Environmental Engineering, and Nanyang

Environment and Water Research Institute, Nanyang Technological University, Singapore.

Tel: +65 6790 5321. Fax: +65 6790 6620


Abstract

Silt screen has been considered the “best management practice” to control the dispersal of suspended

sediment at dredging and reclamation sites. As a vertical, flexible structure that extends downward

from the water surface to the prescribed depth, the flow in the vicinity of a silt screen base on the

prevailing design shows three dominant flow patterns: a retarded flow region in the upper water layer

upstream of the screen, a large recirculation zone being formed in the upper water layer downstream

of the screen, and a fast underflow formed beneath the silt screen. These flow patterns significantly

affect the distribution of sediment, containment and settlement in the silt-screen enclosed area. Two

parameters were identified as the determining factors to achieve effective sediment containment in the

upstream region of a silt screen, and they are: (1) the extent of the upstream retarded flow and (2) the

magnitude of the fast flow. This paper discusses the effects of configurations of silt screen on the flow

characteristics that determine sediment redistribution. The results were obtained from literature

review of relevant studies and numerical studies on the effects of screen configurations on the flow

patterns.

Keywords: Suspended sediment containment, Silt screen, Dredging, Reclamation



153

SECM/13/167

LAND RECLAMATION IN SINGAPORE: FROM RESEARCH TO PRACTICAL

APPLICATIONS

Jian Chu1, Jia He

2, Kok Pang Lam

3, and Soon Keat Tan

4

1School of Civil and Environmental Engineering, Nanyang Technological University, Singapore

Telephone: +65-6790-4563



Telephone: +65-6790-6619


3JTC Corporation, Singapore

Telephone: +65- 6883-3823



Telephone: +65-6790-5321


Abstract

Limited land space and the demand for space to cater for the rapid economic development have led to

large-scale land reclamation in Singapore since early 1970s. In this paper, the authors first present an

overview of the land reclamation history in Singapore. In recent years, the scarcity and increasing

price of conventional land-fill materials including sand and gravel, have become a challenge and new

problem for large-scale land reclamation. The use of alternative fill materials need to be resolved

quickly and their use certified and accepted by the relevant authorities. Materials that can potentially

be used include clay slurry, lumpy soil, cemented clay, and some industrial and domestic wastes such

as sewage sludge and copper slag. An overview of the technical considerations regarding the use of

these materials in land reclamation is presented. Some recent research studies of methods of land

reclamation which could be applied in practice are also presented.

Keywords: Land reclamation, Fill materials, Soil improvement

154

SECM/13/168

A VARIATIONAL BOUNDARY ELEMENT APPROACH FOR STRAIN GRADIENT

ELASTICITY

N. A. Dumont, D. Huamán Mosqueira

Department of Civil Engineering, Pontifical Catholic University of Rio de Janeiro

22451-900 Rio de Janeiro, Brazil

Telephone: 5521993165366; Fax: 552135271195


Abstract

The mathematical modeling of microdevices, in which structure and microstructure have

approximately the same scale of magnitude, as well as of macrostructures of markedly granular or

crystal nature (microcomposites), demands a nonlocal approach for strains and stresses. The present

paper starts from Mindlin‟s strain gradient theory, based on three additional constants for

homogeneous materials (besides the Lamé‟s constants), to arrive at a proposition made by Aifantis

with just one additional parameter. This simplified proposition has also been applied mainly by

Beskos and collaborators in the context of the boundary element formulation. It is shown in the

present paper that a hybrid variational approach – as proposed by Pian and generalized by Dumont for

finite and boundary elements – seems to provide a natural conceptual framework to properly deal

with the interelement compatibility of the normal displacement gradients of the strain gradient

elasticity, in which “corner nodes” are not an issue. Nonsingular fundamental solutions – domain

interpolation functions – have already been obtained by the authors for two-dimensional (2D) and

three-dimensional (3D) problems, with the generation of families of finite elements that may be

implemented in a straightforward way. However, such a finite element implementation does not seem

to be practical, since too many domain degrees of freedom turn out to be required even for some

simple numerical analyses. The singular fundamental solutions needed in a boundary element

formulation are rederived and conceptually assessed. Since the experimental data available in the

technical literature are still scarce and the numerical results are mostly questionable, consistency is

assessed by means of patch tests and by investigating the spectral properties of the matrices derived

for some 2D plane strain application problems.

Keywords: Gradient elasticity, Variational methods, Hellinger-Reissner potential, Hybrid boundary

element method.

155

SECM/13/169

OPPORTUNITY FOR USAGE OF GRIT FOR CONCRETE AND CEMENT PRECAST

PRODUCTS INDUSTRY

M. S. T. Priyadarshana, G. Chandrasena, P. B. R. Dissanayake



2Holcim (Lanka) Ltd


3Department of Civil Engineering, University Of Peradeniya, Sri Lanka


Abstract

There has been increasing concern in recent years about pollutants generated by the ship building and

repair industry. In particular, abrasive blast media, metals, metal related compounds, petroleum

associated hydrocarbons and antifouling ingredients in paints have come under scrutiny.

The shipbuilding and repair industry presents a unique problem in terms of applying pollution control

techniques. There are several different functions that occur at ship and boat repair facilities. Some

facilities employ a few people, while others employ many people, including various subcontractors,

blacksmiths, boilermakers, chemists, carpenters, electricians, labourers, machinists, welders, painters,

sandblasters, riggers, pipefitters and a number of administrative and managerial staff. A tremendous

amount of spent blast abrasive dust and grit is generated daily.

There are hundreds of smaller shipyards and marinas which service small commercial and private

boats, in addition to large shipyards which service from small vessels and marine equipment to super

structures. Abrasive blasting at repair facilities presents an especially challenging task in terms of

pollution control because this activity results in a very fine airborne dust which is difficult to contain,

it is generated in large volumes, and it takes place near water resources. Add to this complexity,

antifouling ingredients which can be deadly to water organisms.

The following components comprise up to 90% of the grit composition.

o Silicon Dioxide 20-50%

o Iron Oxide 40-70%

o Aluminium Oxide 0-25%

o Calcium Oxide 0-25%

In Sri Lanka annual collection of Grit is around 6000MT and usage of Grit is a huge problem in

nowadays.

Holcim Innovation & Application centre performed lab trails for various concrete grades and precast

products. As the second step industrial trials also performed with the ready mix plants. It was found

that Up to 20% of Grit can be replaced by the sand without any abnormalities for the physical

parameters.

Keywords: Grit, recycle materials in concrete, sustainable concrete



156

SECM/13/170

MONITORING THE TEMPERATURE RISE IN MASS CONCRETING

M. S. T. Priyadarshana, G. Chandrasena, P. B. R. Dissanayake



3Department of Civil Engineering, University Of Peradeniya, Sri Lanka


Abstract

The temperature rise in the interior of a thicker concrete mass due to the heat development by the

hydration of cement can lead to the serious of cracking and adversely effect of the strength and

durability of concrete.

Experimental tests were carried out to investigate the temperature rise characteristics of Fly Ash

cement and OPC cement concrete under semi-adiabatic conditions.

For the evaluation of temperature rise and distribution in mass concrete blocks tested at university of

Moratuwa, Hocim Innovation and Application Center and the On Three20 project (Estimated total

concrete volume for whole project is around 60,000 m3).

In the measuring process we considered the following factors; cement content, insulation materials,

placing temperature of concrete, etc. On the temperature rise and distribution in a mass concrete mock

up block were discussed.

Test results found that the concrete with more than 25% Fly Ash replacement in cement exhibited a

significant decrease in the peak value of the temperature rise and maximum temperature rise rate. The

results of the numerical simulation showed that the temperature development and distribution profile,

which is directly contributed from the heat of hydration of cement with time, is significantly affected

by the selection of insulation, placing temperature and construction procedures.

Keywords: mass pouring, mass concrete, Fly Ash cement, adiabatic condition, Temperature rise



157

SECM/13/171

DEVELOPMENT OF OPTICAL FIBER SENSORS FOR THE PERFORMANCE OF

STRUCTURES

1Jian-Hua Yin,

2HF Pei,

3DS Xu,

4CY Hong,

5HH Zhu

1,2,3,4,5Department of Civil and Environnemental Engineering, The Hong Kong Polytechnic University,

Hung Hom, Kowloon, Hong Kong, China

Tel: (852) 2766-6065, Fax: (852) 2334-6389


Abstract

In the past few decades, a variety of instruments have been developed and used for measuring strains,

inclination angles and displacements of various structures. Conventional sensors such as vibrating

wire strain gauges (VWSG) and electrical resistance strain gauges (ERSG) are still popular for

geotechnical health monitoring. These conventional sensors are found to have poor long-term

durability and low resolution, leading to measurement errors. To overcome these limitations of

conventional instruments, a significant improvement has been made on the development of fiber

Bragg grating (FBG)-based sensors for measurement of tilts and displacements of geotechnical

structures. The FBG sensors are not only an alternative approach for monitoring the performance of

geotechnical structures, but also have advantages over conventional sensors, such as high accuracy,

multiplexing capability, electromagnetic interference resistance and durability.

In this paper, five types of FBG-based sensors developed by the authors will be introduced:

(a) Special strain gauges for monitoring strains in concrete and flexible pavement.

(b) FBG-based tilt sensors for monitoring inclination angle of a structure.

(c) FBG-based in-place inclinometer for monitoring international displacements in a slope or

ground.

(d) FBG-based beam sensors for monitoring lateral deflection of a soil mass in shaking table

tests.

(e) FBG-based beam sensors for monitoring settlement of flexible pavement.

In this paper, the authors present the working principles, designs, calibrations, and applications of the

above five FBG based sensors for measuring strain, tilts, and internal displacements and settlements

of structures. The advantages over previous conventional and FBG sensors and limitations are also

presented.


158

SECM/13/173

USING NONLINEARITY OF PIEZOELECTRIC MATERIALS UNDER STRONG FIELD

ACTUATION FOR ACTIVE VIBRATION CONTROL OF COMPOSITE STRUCTURES

M. Yaqoob Yasin, Santosh Kapuria

Department of Applied Mechanics, Indian Institute of Technology Delhi, New Delhi 110016


Abstract

In this work, we present a computationally efficient finite element (FE) model for active vibration

control of smart composite and sandwich shallow shells integrated with piezoelectric sensors and

actuators, considering their nonlinear characteristics under strong electric field. The nonlinearity is

modeled using the rotationally invariant nonlinear constitutive equations of Tiersten (1993), with the

assumption of large electric field and small strains. The FE is based on the fully coupled zigzag

theory, which has accuracy similar to the layerwise theories, but retains the economy of the equivalent

single-layer theories, with only five displacement unknowns. The nonlinear equations are derived

using the extended Hamilton‟s principle of virtual work. For static shape/stress control analysis, these

equations are solved using the direct iteration method. The results predicted by the nonlinear model

compare very well with the experimental data available in the literature for static response. The effect

of piezoelectric nonlinearity on the predicted control voltage required for reduction of deflection or

stresses, as well as on the sensory potential induced under mechanical and electric potential loadings

has been examined for the hybrid shells. The effect of the piezoelectric actuator thickness ratio on the

nonlinear actuation potential required for static deflection control is also studied. For active vibration

control, the FE model is transformed to the reduced order modal space considering first few modes

and expressed in the state space form. The resulting nonlinear control problem is solved using LQG

controller through feedback linearization of the control input. The control response is obtained for

transient vibration under step and impulse excitations, as well as steady state vibration under

harmonic excitation. The effect of the piezoelectric nonlinearity on the active vibration control is

studied for hybrid composite and soft-core sandwich shells. It is shown that the linear model

significantly overestimates the peak control voltage required to achieve a given settling time. Thus,

using the piezoelectric nonlinearity, the vibration control can be achieved at a much lower actuation

potential than predicted by a linear model. It is seen that, while in the linear model, the control voltage

for a given settling time is almost independent of the actuator thickness (Figure 1), the actual control

voltage predicted by the nonlinear model reduces significantly as the actuator thickness decreases.

Figure 1: Variation of peak control

voltage as a function of actuator thickness

159

SECM/13/174

APPLICATION OF HIGH-PERFORMANCE STEEL TO GIRDER OF

COMPACT I-SHAPED SECTION

E. Yamaguchi1, Y. Sugimura

1, K. Ohmichi

1

1Department of Civil Engineering, Kyushu Institute of Technology, Japan

Telephone: +81-93-884-3110; Fax: +81-93-884-3110


Abstract

In 2008, high performance steels were registered in JIS (Japanese Industrial Standards): SBHS500 and

SBHS700. They are high strength steels developed specifically for bridge construction. In addition to high

yield strength, they have various advantages such as good weldability over conventional steels. Therefore

they are also known as high-performance steels.

Focusing on the high yield strength, the present study explores a possibility of their effective use. To this

end, the maximum width-to-thickness ratios for compact I-shaped sections are first obtained for various

yield strengths and shapes by nonlinear analysis. These maximum width-to-thickness ratios are quite

different from those in AASHTO. The present study further investigates the cause for the difference, which

turns out to be attributable to difference in initial imperfection and stress-strain relationship.

Then considered are two homogeneous sections and one hybrid section. The homogeneous sections are

made of SM490Y and SBHS500, respectively, and the hybrid section is of SM490Y for a web and

SBHS500 for flanges, where SM490Y is a conventional steel in JIS. The three sections are designed for a

given plastic moment. The design of each cross section is carried out so as to minimize the weight. The

homogeneous section of SBHS500 is found the lightest: 19％ less than the weight of the homogeneous

SM490Y section. Yet the price varies from steel to steel. From the viewpoint of material cost at the

moment, the hybrid section is the most competitive.

Keywords: Steel girder, Compact I-shaped section, High-performance steel, Hybrid girder, Optimum

section


160

SECM/13/175

MULTISCALEMODELINGOFFIBER-REINFORCEDCOMPOSITES

P. Kumar1, M. Ajugia

2, G. Bharat

3, N. K. Naik

4, Y. M. Desai

5

1,4

Department of Aerospace Engineering, IIT Bombay, Powai, Mumbai 400076, INDIA

2,3,5

Department of Civil Engineering, IIT Bombay, Powai, Mumbai 400076, INDIA


Abstract

Composites are increasingly becoming a material of choice for consumer goods, biomedicaldevices

and construction besides the high-performance applications in the aerospace and automobile

industries. Efficient utilization of a composite can only be assured by a designthat considers material

properties accurately. Computational simulations and refinements inanalysis techniques are motivated

by the need to replace the physical testing of components,and are supported by the enhanced

capabilities of the modern computers. Physical testing atthe macro level cannot capture the complete

behavior of a composite, which is inherentlyheterogeneous at the microscopic scale. A sequential

approach to the prediction of the elasticand strength properties at the micro, meso and macro levels,

known as multiscale modeling,is presented here. The multiscale approach, which serves as a bridge

between themicromechanics and the continuum mechanics, ensures that the homogenized properties

arederived from the well-defined properties of the constituent phases of the composite.

Strengthanalysis of composites is possible by multiscale modeling as it allows the inclusion ofdamage

criteria into the model. The approach becomes more significant for analyzing 3Dfiber-reinforced

composites that have considerably better properties in the thickness directionthan the 2D laminates.

The micromechanical analysis of the repetitive unit cells (RUCs), along with the periodicboundary

conditions, initiates the computation of homogenized properties of the composites.The variety of fiber

topologies in a 3D composite results in a number of unit cells. The model must also simulate the

random distribution of the micro RUCs in the transverse direction inactual macrostructure. The

damage criteria can be incorporated by employing contactconditions or interface elements between

the reinforcement and the matrix in the FEM modelof the RUC. In this paper, a brief review of the

multiscale modeling techniques for fiberreinforcedcompositesis presented.Anoverviewof the

Selectionof RUCsformicromechanical analysis and the assignment of appropriate periodic boundary

conditions isgiven. Results of multiscale modeling of 3D woven fiber-reinforced composites for the

effectof fiber distribution on the elastic and strength properties are also presented.


161

SECM/13/176

EFFECT OF VARYING SOURCE OF RECYCLED AGGREGATE ON CONCRETE

PROPERTIES BY EXPERIMENTAL EVOLUTION

Parekh D. N1, Modhera C. D

2

1Applied Mechanics Department, SVNIT, Surat


2Applied Mechanics Department, SVNIT, Surat


Abstract

A popular concrete mix 0.5:1:1:2 was used here for experimental purpose. Recycled coarse aggregates

(RCA) were prepared from these concrete after 28 days curing called as known source aggregates.

These aggregates were compared with their corresponding natural aggregates, unknown source RCA

and Indian Standard (IS) requirements. Concrete mix was prepared by replacing 0%, 10%, 20%, 30%,

50% and 100% of known and unknown source RCA. Thus total twelve trials were prepared and the

effects of RCA on fresh and hardended properties have been established. Fresh and hardended

properties of concrete were determined. Some improved new equations are proposed for the

prediction of the relations between the mechanical properties of RAC based on the statistical

regression analysis with the least squares method.

Keywords: Recycled Aggregates (RA), Recycled concrete aggregates (RCA), Recycled Aggregate

concrete (RAC),


162

SECM/13/177

SUB-SURFACE IMAGING OF MATERIAL MEDIUM USING SYNTHETIC APERTURE

FOCUSING TECHNIQUE (SAFT)

Abhishek Dhawan

Department of Civil Engineering, Indian Institute of Technology (IIT) Delhi, India.

Telephone: 08800264816;


Abstract

Ultrasonic Techniques are widely used for sub-surface imaging in non-destructive testing (NDT) of

materials for detection of flaws, defects in material media. Ultrasonic inspection also provides information

about material characterization and dimensional measurements of the medium. Thus, it finds wide

application in various areas of engineering, viz. forensics, structural and civil engineering, mechanical

engineering, systems engineering, aeronautical engineering, medicine and art.

Synthetic Aperture Focusing Technique (SAFT) is an algorithm that uses wave velocity and wave

transmission information to locate defects with enhanced precision. Traditionally, the SAFT employs the

scattered compressional wave (C-C) for sub surface imaging of the medium. Literature review, by using

MATLAB simulations, shows that the quality of imaging and probability of locating the defect is increased

if all mode conversions of the waveform, viz. C-C, C-S, S-C, S-S (C- Compression, S- Shear), are utilized.

This research aims to check the validation of the results in literature by actual experimentation. Ultrasonic

testing of a homogenous acrylic block of known dimensions and defect location is performed and

waveforms are obtained using pulse-echo mode. Data is analyzed to obtain the compressional and shear

wave velocity and lame‟s constants for the medium. B-scans are generated using MATLAB, which are used

as an input for SAFT to generate sub-surface images of the defect. It has been observed that the use of

scattered compressional wave (C-C) produces a sharper image of the defect than the case where all modes

of wave conversion are used.

This study is a part of a wider project to advance the state-of-the-art technology available for non-

destructive testing and sub-surface imaging of material media by using concepts of wave propagation, wave

mode conversions and digital signal processing.

Keywords: Non-destructive testing, SAFT, sub-surface imaging, pulse-echo mode, B-scans


163

SECM/13/178

CYCLIC BEHAVIOUR OF RC BEAMS CONFINED WITH GEOGRID AND STEEL FIBER

R.Siva Chidambaram1, Pankaj Agarwal

2

1.

Department of Earthquake Engineering, IIT Roorkee, India

Telephone: +91-9634430889


2. Department of Earthquake Engineering, IIT Roorkee, India

Telephone: +91-1332-285317


Abstract

This paper presents an experimental investigation on reinforced concrete (RC) beams constructed

with partial geogrid confinement and steel fiber reinforced concrete (SFRC). The effect of geogrid

confinement and SFRC on inelastic behaviour of RC beams has been studied under single point

compression cyclic loading. Three beams with different material configuration have been used and

test was performed on 1000mm long RC beams. The test results shows that a significant improvement

in the post cracking behavior in shear deficient beams due to geogrid confinement as compared to

conventional confinement. The test results also exhibits a noticeable improvement in load- deflection

behaviour of beam and its ductility. A threefold increase in energy dissipation and significant

enhancement in deflection of beam with geogrid and steel fiber has been observed as compared to

conventional beam.

Keywords: High Performance Materials, Steel Fiber Reinforced Concrete, Geogrid Confinement.



164

SECM/13/179

STRENGTHBEHAVIOUR OF SCC WITH POND ASH AS PARTIAL REPLACEMENT TO

FINE AGGREGATE

Bharathi Ganesh1, R Nagendra

2,.H Sharada Bai

3, M R Suresh

4,Harisha C

5, Krishna K L

6

1Global Academy of Technology. Bangalore, Karnataka, India

Telephone: +91 9481034559


2Faculty of Engineering – CIVIL, UVCE, Bangalore University, Karnataka, India

Telephone: +91 9341213638


3Civil-Aid Technoclinic Pvt. Ltd, Bangalore, Karnataka, India

Telephone: +91 9880926050


4Department of Civil Engg. Dr. AIT, Mallathahalli, Bangalore, Karnataka, India

Telephone: +91 9844123174


5,6

MIT Manipal, Udupi, and Dr. AIT, Bangalore, Karnataka, India


Abstract

Self Compacting Concrete, an innovation in concrete, developed in late 1980‟s in Japan, is addressing

infrastructural challenges of site. By 2000, SCC had become popular in Japan. Investigations on SCC

are still in progress to study and understand the dual characteristic properties in fresh state and in the

hardened state with new materials as an alternative to constituent of SCC. Use of Pond Ash, a by-

product of Thermal Power Plant is one such effort to produce SCC replacing sand in different

percentages.

This paper deals with SCC mixes with a cementious content of 400kg/m3 replacing Manufactured sand with

Pond Ash in replacement levels of [0,10, 20, 30, 40, 50] % by weight. SCC mixes designed by Absolute

Volume method were tested for its rheology. SCC mixes though satisfied the rheological requirements as

per EFNARC 2005, no specific behaviour pattern corresponding to replacement levels was observed and

mixes were slightly harsh. However 28day compressive strength upto 30% replacement was comparable

with that of Normal SCC. The strength at 50% replacement level, for SCC with 400kg/m3 cementitious

content was around 20 MPa, proving potential utilization of Pond Ash in SCC as an alternative material for

sand which contributes to sustainable construction.

Keywords: Self Compacting Concrete, Pond Ash, Alternative Material, Compressive Strength, Fine

Aggregate.



165

SECM/13/180

FINITE ELEMENT ANALYSIS OF HISTORICAL STRUCTURES : CASE STUDY ON

GOLGUMBAZ OF BIJAPUR

Shanawaz Kazi1,S.B.Vanakudre

2

1Department of Civil Engineering, SDMCET, Dharwad, Karnataka, India

Telephone: +919880991888


2Department of Civil Engineering, SDMCET, Dharwad, Karnataka, India

Telephone: +919480504837


Abstract

The Historical Structures and Monuments (HSM) in any country are mute testimonials of its glorious past.

A large number of HSM in India are facing extinction and with them will vanish remainders of civilization,

which once upon a time flourished in India. These HSM are like a chapter of a history book and it must not

be allowed to close. Each of these HSM should thoroughly and systematically be examined and analyzed

before arriving at preservation. In particular, simple mathematical models are described, which may help in

locating the exact source of trouble. These models show that the distress in one location may come from a

cause, which is located far away. In actual practice, the load transfer mechanism may be more complicated

then these simple analytical models. This can be handled by using the advanced analytical technique such as

the Finite Element Method. In present Gol Gumbaz of bijapur is taken as the case study. The methodology

adopted for the study which includes mathematical modeling of the structure using finite element method

from Catia v 5 and Hyper mesh v11 software, analysis using MSC Nastran solver for the purpose of

assessment and study of its behavior. The methodology adopted for the study which includes mathematical

modeling of the structure using finite element method from Catia v 5 and Hyper mesh v11 software,

analysis using MSC Nastran solver for the purpose of assessment and study of its behavior.The model

prepared is subjected to Dynamic analysis and various mode shapes are found and frequencies and

fundament time period is calculated. Static Analysis is performed to find out the displacement, stress and

strain of the structure due to seismic pressure.

Keywords: Finite Element method, Dynamic analysis, static analysis, stress, strain


166

SECM/13/181

COMPARISON OF SLANT SHEAR METHOD AND CDM METHOD (DIRECT SHEAR)

FOR BOND BETWEEN REPAIR MATERIALS AND PARENT CONCRETE

Kamlesh S.Dalal1, C.D.Modhera

2, S.A.Vasanwala

3

1Applied Mechanics Department, SVNIT, Surat, Gujarat, INDIA.









Abstract

Good bonding between repair materials and concrete substrate is of vital importance in the concrete repairs.

Repairing concrete structure is a composite system of materials and in composites the bond between the

individual components is most critical for overall capability. The durability of the bond in repair systems

can be defined as a lasting interfacial coexistence of repair and existing phases (old substrate

concrete). Assuming the properties of the both surfaces are good, any improvement of the bond will

improve the properties of the composite system. Achieving a satisfactory bond between repair materials and

existing concrete is a vital need for durable surface repairs. It is essential that the repair material

accomplishes a strong bond to the substrate and that subsequent stresses not be harsh enough to cause

debonding. Present Study deal with using PMM(SBR), PMM(Acrylic), Microconcrete as repair materials to

study bond with substrate concrete, comparison of two methods slant shear method and CDM

method(Direct Shear) for bond strength (Shear Strength) also studied using these repair materials.

Keywords: Bond Strength, substrate concrete, various repair materials, Slant Shear, CDM method (Direct

Shear)







167

SECM/13/182

AN EVALUATION ON THE IMPLEMENTATION OF ISO 50001:2011

ENERGY MANAGEMENT SYSTEM (EnMS) IN THE SRI LANKAN CONTEXT

S.B.R.G.K.. Samarakoon1,P.A.D. Rajini

2


Telephone: +94 775 465 477




Abstract

Throughout the world, energy conservation is ranked as a high priority on the environmental agenda,

because energy is a demanding resource for organisational operations and can have a significant

impact on organisational economic condition. Instead of economic problems, energy crisis can

impose various environmental and societal costs by reducing resources and supporting

environmental problems. Over the entire life cycle, building has been identified as main energy

consumer in the world.Hence, energy is considered as one of the main cost centres for building

operations. Considering the importance of managing energy, a number of national, regional and

international Energy Management Systems (EnMSs) have been developed to integrate energy

efficiency into organisations‟ management practices, while fine-tuning operating processes and

improving efficiency of industrial systems. However, literature and preliminary studies revealed that

there are very few ISO-50001:2011-EnMS applications within Sri Lanka. Hence, there is a little

doubt relating to the implementation of ISO 50001:2011-EnMS in Sri Lankan Context. Therefore,

the aim of this research was to evaluate the adoptability of ISO 50001:2011-EnMS in the Sri Lankan

context.

Literature review, preliminary expert survey and multiple case studies were employed in achieving

the aim of the research. A conceptual framework for implementing ISO 50001:2011-EnMS was

developed after the literature review and it was revised with the preliminary expert survey findings.

Research findings revealed that the entire EnMS is fully compatible with Sri Lankan context.

Further, results from this study discussed organisational and system requirements, importance and

objectives of implementing ISO 50001:2011-EnMS in Sri Lanka, enablers and barriers of

implementation, and recommended practices for proper implementation process. According to the

findings, „time consuming procedures for achieving the certification‟, „development of EnPIs‟,

„hidden costs‟, and „non-availability of competent persons internally‟ could be identified as ruling

barriers at the implementation stage. The study also found a number of drivers; „involvement and

support of top management‟, „past record keeping‟, and „assertiveness on energy cost reduction‟, as

motivators for implementing ISO 50001:2011-EnMS. Finally, the research developed a framework

for implementing ISO 50001:2011-EnMS in the Sri Lankan context with several recommendations

on implementation.

Keywords: Energy Management, ISO 50001-EnMS, Sri Lanka





168

SECM/13/183

A REVIEW OF FACTORS AFFECTING USER ATTITUDES AND BEHAVIOUR ON

WATER CONSERVATION IN HOTEL FACILITIES

Damitha Rajini1, Y.G. Sandanayake

2


Telephone: +94 770 640 075



Telephone: +94 772 519 110


Abstract

Water is a resource with high ecological and social value, and vital for the survival of our planet Earth. It

determines the quality of living and important for most of the social and economic activities. Although the

Earth‟s surface is composed by two-thirds of water, only 1% of the existing water is available for human

consumption. Further, continuous growth of population, economic development and increasing human

needs have stimulated the water demand into unexpected levels. Therefore, today, water has become a

scarce and expensive resource. As a major subsector of the tourism industry, the hotel sector accounts for a

huge amount of water for its daily operations, being an intense user of water resource. User attitudes and

behaviour towards water conservation has a significant impact on water consumption in hotel facilities.

Apart from environmental concerns, water related attitudes and behaviour of people are affected by many

factors such as personal preferences, comfort, cleanness, technologies and design, financial capabilities,

knowledge, and education, to name few. Therefore, understanding the impact of such behavioural factors is

crucial to develop appropriate water saving strategies focused on attitudinal and behavioural change.

Alhough, user behaviour has a very high impact on water consumption in hotel buildings, there is a lack of a

comprehensive research in the area of factors affecting user bahaviour on water consumption in hotel

facilities. Therefore, the aim of this paper is to review factors affecting user attitudes and bahaviour on water

consumption in hotel facilities. A comprehensive literature review will be carried out to identify attitudinal

and behavioural factors affecting water consumption in hotel facilities. The literature findings will be used

to develop a conceptual model in the next phase of study.

Keywords: Water Conservation, User Attitudes, User Behavior, Hotel Facilities



169

SECM/13/184

MECHANICAL PROPERTIES OF AMBIENT CURED GEOPOLYMER CONCRETE

Radhakrishna

Dept of Civil Engineering, R V College of Engineering, Bangalore, INDIA

Telephone:+919886127398; Fax: +9108028600337

E mail: [email protected]; [email protected]

Abstract

Geopolymer concrete is an alternate material to the conventional concrete. The research on heat cured

geopolymers is well documented by multiple researchers. However, there is very little information

available on ambient cured geopolymer concrete. This paper illustrates the mechanical properties of

ambient cured geopolymer concrete prepared from Class F fly ash and ground granulated blast

furnace slag with alkaline activator solution. Various mechanical properties like compressive, split

tensile, flexural, shear, impact and bond strength of ambient cured geopolymer concrete were

determined. Stress-strain behavior was also studied. Sample durability tests of conventional and

geopolymer concrete were investigated and compared. It was found that many properties of ambient

cured geopolymer concrete were superior when compared to conventional concrete. It was concluded

that geopolymer concrete can be used as high performance concrete in place of conventional concrete

for structural applications with many advantages.

Keywords: Fly ash, slag, geopolymer, concrete, mechanical properties.


170

SECM/13/185

SIMPLE DELAY ANALYSIS METHODOLOGIES SELECTION ADVISOR FOR

CONSTRUCTION PRACTITIONERS (DAMSA)

Ibrahim Nasr1, Sherif Hafez

2

1Structural and Construction Department,Alexandria University, Egypt

Telephone:00966563060740


2Structural and Construction Department, Alexandria University, Egypt


Abstract

Delay analysis is one of the constructions industry dilemmas. Several researches and best practices

have been developed to deal with this issue but none of the current techniques responds accurately to

all of the four common delay issues: real time delay, concurrent delay, acceleration, and pacing delay.

In addition most of the researchers did not accommodate the construction management conditions and

levels. In fact even if CPM is implemented in the project many projects are not following the CPM

and many projects are not implementing CPM. Most of the current researches and practices

concentrate only on CPM or on Non CPM.

In most cases the two parties in many of the construction projects even though the mega and multi-

billion projects in North Africa and the Middle East try to find the simplest method to calculate the

delay and the extension of time although of the presence of their armies of project management

professionals.

At the beginning I have tried to develop an expert system by integration of Primavera Project

Management, Primavera Contract Management and Knowledge Base. Many factors and the huge

amount of variables moreover the complexity that shall face the user declined this approach.

Through the experiences and the survey answered by hundreds of professionals it's clear that most of

the construction practitioners have no idea about delay analysis even most of the experienced planners

who are in most cases schedulers were not able to monitor neither ability nor knowledge about this

subject.

This paper shall focus of presenting an easy method to select the delay analysis methodology that may

fit the case meanwhile shall present a tool to enrich the schedulers knowledge about the subject.

Keywords: Construction Delay Claims, Delay Analysis Technique, Construction Disputes

171

SECM/13/186

THEDISPLACEMENTOFSOILNAILINGSLOPESREINFORCEDWITHUNDERDYNAMIC

LOADS

Sina Hajati Ziabari1, Ali Abdollahi

2

1Department of Geological Engineering, Ferdowsi University, Iran

Telephone:+98 9111390826; Fax: +98 1312221957


2Department of Civil Engineering, Islamic Azad University Arak Branch, Iran

Telephone: +98 9373783761


Abstract

An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic

waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of

earthquakes experienced over a period of time. Iran is one of the most seismically active countries in

the world, being crossed by several major fault lines. that cover at least 90% of the country. As a

result, earthquakes in Iran occur often and are destructive. Soil nailing is a construction technique that

can be used as a remedial measure to treat unstable natural soil slopes or as a construction technique

that allows the safe over-steepening of new or existing soil slopes. The technique involves the

insertion of relatively slender reinforcing elements into the slope – often general purpose reinforcing

bars (rebar) although proprietary solid or hollow-system bars are also available. Today the soil nailing

widely used for excavation and slope stabilization. Soil nailing was increases the shear strength of the

soil mass and limited soil mass failure. In this article, an issue was important is the effects of dynamic

forces on nailing system. Therefore it is important behavior of soil nailing system under earthquake

force. Maximum horizontal and vertical displacement of accelerograph between nails and soil with

simulated using finite element method and modeled with ABAQUS software. The parametric study

has been conducted on factors affecting horizontal and vertical displacement of the soil nailed slope

was shown increase Cohesion and friction angle of the soil parameters and modulus of elasticity,

Maximum horizontal and vertical displacement between the nail and the soil was less, The friction

angle of the soil, reducing displacement and effective than the soil cohesion and modulus of elasticity.

Also, the height of slope and space of nail effectively maximum horizontal and vertical displacement

between the nails on the nails when increasing height of slope, the displacement was increased and

increasing space of Nails, has been select reasonable distance.

Keywords: Earthquake, Soil nailing, Slope, Displacement




172

SECM/13/187

FLAW BRIDGING IN UNIDIRECTIONAL FIBRE-REINFORCED COMPOSITES:

IMPLICATIONS ON FRACTURE AND FAILURE

A.P.S.Selvadurai

Department of Civil Engineering and Applied Mechanics, McGill University

817 Sherbrooke Street West, Montreal, QC. H3A 21K6, Canada


Abstract

Unidirectional fibre-reinforcement is used in engineering applications when strengthening of a

structural component needs to be made in a pre-defined direction. Although such loading conditions

are rare, the study of unidirectionally reinforced composites provides a useful assessment of the

contributions of the reinforcing fibres to the overall performance of the composite. The fracture and

failure of unidirectionally reinforced composites is therefore of particular interest when assessing

their structural integrity. In this paper, we examine the type of defects where the matrix region is

either absent or a crack has developed in the matrix of the unidirectionally reinforced composite but

continuity of the fibres is maintained across the boundary of the matrix-depleted region. This fibre

continuity across the defect can impose a deformability constraint that can alter the stress state around

a three-dimensional defect and the stress intensity factor at the boundary of a crack. In this paper, the

results for two types of flaw-bridging problems will be investigated and will show how the tensile

stress state at the boundary of a three-dimensional flaw and the stress intensity factor at the edge of a

penny-shaped crack can be influenced by the bridging action.

Keywords: Unidirectional reinforcement, matrix defects, fibre continuity, stress , Effective thickness,

Maximum corroded depth, Remaining strength

173

SECM/13/188

CYCLIC BEHAVIOUR OF LOW YIELD STEEL SHEAR LINK

K. Baskar1, S. Bathrudeen Syed Ishak

2, P. V. Premalatha

3

1Department of Civil Engineering. N.I.T., Trichy, India – 620015

Telephone: +91-9790180736


2Department of Civil Engineering. N.I.T., Trichy, India – 620015

3Department of Civil Engineering, CARE School of Engineering., Trichy, India – 620009


Abstract

Use of energy dissipation devices in view of reducing the seismic induced damage is becoming more

popular in the recent scenario in the earthquake resistant design of structures. Shear panels made use

of ductile metals are one of the efficient energy dissipation devices. Low yield steel could dissipate

considerable amount of energy under earthquake loading due to its large deformation capacity without

compromising the elastic stiffness of the structure. In this present study, cyclic behaviour of shear

links made using low yield strength steel (102 MPa) has been studied with wide range of parameters

through non-linear finite element model. The general purposed finite element analysis software

ABAQUS is employed in this study to carry out the non-linear cyclic load analysis on portal frame

provided with low yield strength shear link. The specimens were subjected to slow cyclic loading and

hysteretic behaviour of the specimens were studied. This paper deals with the details of the study such

as parameters considered, finite element modeling that includes geometric and material non-linearity

and the analysis procedure. From the results obtained, the Gerard‟s proportionality factor ( ) which

gives the limitation on aspect ratio and web depth to thickness ratio of shear panel to avoid inelastic

buckling at desired strain level is suggested.

Keywords: low yield steel, shear panel, Abaqus, inelastic buckling, energy dissipation


174

SECM/13/190

FORECASTING DETERIORATION OF BRIDGE ELEMENTS FROM VISUAL

INSPECTION DATA

1Md Saeed Hasan,

2Sujeeva Setunge,

3David W Law

1School of Civil, Environmental and Chemical Engineering, RMIT University

Telephone: +61425806535






Abstract

In order to extract the optimal output in the form of good management decisions with least resources,

a bridge management system or BMS in short, is an essential part for every road transport authority.

In BMS, decisions regarding frequency of maintenance, conductingrepairs and rehabilitation are

based on inspection data collected for the bridges using a condition rating manual. The road

authorities are constantly trying to convert these condition monitoring data to a meaningful practical

decision supporting tool. To address this need, a comparison of two most popular methods namely

Markov chain and artificial neural network has been deployed for same set of observations.

Visual inspection data has been sourced from the road transport authority of Victoria, Australia and

transition matrix has been derived using Non-linear optimisation techniques of Markov chain model

to predict the future condition of bridge elements. On another attempt ANN were deployed to perform

prediction using same set of data and compared with the Markov model. Outcomes indicate that the

both methods offer a reasonable solution to the decision making requirements.

Keywords: Condition Monitoring, Artificial neural network, Bridge deterioration, Markov Chain




175

SECM/13/191

UTILIZATION OF WASTE TYRE IN MANUFACTURING OF NON-STRUCTURAL

CONCRETE

P. V. Premalatha*1, A. Jennifer

2 ,S. Shree Janarthanan

3

1Department of Civil Engineering, CARE School of Engineering, Tiruchirappalli,

India.Telephone: +91-9944579386


2Department of Civil Engineering, CARE School of Engineering, Tiruchirappalli, India.


3MAGA Engineering PVT Ltd, Colombo, Srilanka.

Abstract

On the basis of statistical data provided by the Environmental Protection Agency (EPA), 270,000,000

millions waste tyres are produced each year. The disposal of the waste tyres in the landfills is the

major issue handled by the local municipalities and government sectors. The statistical study also

gives an estimate that within the next decade the majority of the landfills used for the waste tyre

disposal shall be closed and this poses the problem of need for lands for waste dumping. This new

problem gave an idea of recycling of waste tyres instead of filling them in bare lands. One such

possible way is to use the waste tyres for the construction industry in the form of tattered rubber or

crump rubber components which can be mixed with as an aggregate or filler. The present work mainly

focuses on finding out the correct proportion of tyre fibres and coir that can be added to concrete to

get enhanced results comparing to conventional concrete. It is observed from the study that, despite a

considerable loss in strength, this type of concrete was acceptable for various applications requiring

medium to low compressive strength such as floor rips, partitions, back stone concrete, concrete

blocks, and other non-structural uses. The quantities of concrete produced worldwide for such

applications could ensure the viability of this product.

Keywords: Used vehicle tyres, Coir, rubberised concrete properties, non structural concrete



176

SECM/13/192

ASSESSMENT OF EFFECTIVE BOUNDARY CONDITION AS A FUNCTION OF

COMPOSITE PLATE GIRDER GEOMETRY

S.Sathiyaseelan1, K.Baskar

2

1Department of Civil Engineering, Erode Builder Educational Trust‟s Group of Institutions, India.

Telephone: +91-9788123733


2Department of Civil Engineering, National Institute of Technology- Tiruchirappalli , India

Telephone: +91- 9790180736; Fax: 0091-431-2500133


Abstract

The web of composite plate girder with its neutral axis lies within the concrete slab will be under combined

action of in-plane shear and tension and prone to delayed shear buckling which in turn mainly depends on

torsion rigidity of web – flange juncture. But in analysis, the juncture is normally assumed as either simply

supported or clamped boundary. Also, the influence of tension is usually neglected. Hence, in this paper, a

numerical (Finite Element) study is carried out to assess the effective boundary condition at web-flange

juncture of composite plate girder, as a function of plate girder geometric parameters. Initially, an isolated

plate girder model is formulated and validated for its further use in the parametric study involving varying

geometric parameters. The resultant elastic shear buckling load is then calculated for each geometric

parameter, using a new form called multi-step buckling analysis in ABAQUS, for the case of combined

shear and tension .In the analysis, the results of simply supported and clamped thin plate model is been used

for checking the convergences of results of plate girder model. From the study, it is found that the upper

shear buckling value of plate girder under any applied tensile load, converges with that of clamped thin

plate. With this convergence, the limiting value for torsion parameters corresponding to simply supported

and clamped condition is formulated for plate of aspect ratio 1 to 3. Also, simplified equation is formulated

using multi- linear regression model and proposed for its use in composite girder, to determine the shear

buckling load for the applied tension and given plate girder geometry.

Keywords: composite, plate girder, shear, tension, buckling


mailto:drkbaskar@

177

SECM/13/193

DAMAGE DETECTION IN REINFORCED CONCRETE BEAMS USING MODAL DATA

V. B. Dawari1, G. R. Vesmawala

2

1 Department of Applied Mechanics, S. V. National Institute of Technology, Surat, India

Telephone: +91-9423003060; Fax: +91-261-2227334


2Department of Applied Mechanics, S. V. National Institute of Technology, Surat, India

Telephone: +91-261-2201808; Fax: +91-261-2227334


Abstract

Civil Engineering structures are prone to damage and deterioration during their service period. Vibration

based damage identification techniques are based on the fact that damage in a structure alters dynamic

characteristics of the structure. The change is characterized by changes in the eigen parameters that are

natural frequency, damping values and the mode shapes associated with each natural frequency. Damage is

identified by comparing the typical dynamic properties of the damage and undamaged structure. In the

present work, methods based on modal curvature and modal flexibility differences are employed for

identifying and locating honeycomb and crack damage in finite element models of reinforced concrete

beams. In order to verify the suitability for implementing algorithms, eigen value analyses are carried out on

finite element models of Reinforced Concrete beam and the eigenvectors for different damage cases are

extracted. Damage is considered as a localized reduction in structural stiffness in case of modeling

honeycomb damage. The crack damage is simulated using discontinuing element model method It is

observed that these methods effectively detected the existence of damage and are able to locate the position

of damage for single and multiple damage scenarios for beams.

Keywords: Crack damage; Modal curvature; Modal flexibility; Reinforced concrete beam


178

SECM/13/194

SEISMIC RESPOSNE CONTROL OF BENCHMARK HIGHWAY BRIDGE USING

VARIABLE FREQUENCY PENDULUM ISOLATOR

1Suhasini N. Madhekar,

2R.S. Jangid

1Department of Civil Engineering, College of Engineering Pune, India


2 Indian Institute of Technology Bombay, Powai, Mumbai - 400 076, India


Abstract

Earthquake response of benchmark highway bridge isolated with an advanced frequency base isolator,

Variable Frequency Pendulum Isolator (VFPI) is investigated under six prescribed earthquake ground

motions. A simplified lumped mass finite element model of the 91/5 highway bridge at Southern

California is used for the investigation. Considering the phase-I benchmark problem, isolators are

assumed to be installed between the deck-ends and abutments. In order to verify the effectiveness of

VFPI, the seismic response of the bridge isolated with VFPI is compared with that of the bridge

isolated with the conventional friction pendulum system (FPS). The seismic response of the bridge is

obtained by solving the governing equations of motion by Newmark‟s step-by-step integration

method. Parametric studies are carried out by evaluating various performance indices to critically

examine the behaviour of the benchmark bridge isolated with the VFPI and FPS; and to find the

optimum values of parameters. The important parameters considered are coefficient of friction and

isolation period of the FPS; and frequency variation factor, initial time period and coefficient of

friction of the VFPI. The response of the bridge with VFPI is analysed and compared with the

corresponding uncontrolled case, with FPS, and that controlled by alternate sample control strategies.

Significant reductions in the base shear, base moment, deck displacements and bearing displacements

are observed using FPS and VFPI. From the investigations, it isconcluded FPS and VFPI are quite

effective in substantially reducing the peak response quantities of the bridge to a level comparable to

that of the sample controllers.

Keywords: benchmark highway bridge; seismic isolation; friction pendulum system; friction

coefficient; variable frequency pendulum isolator



179

SECM/13/195

ULTIMATE LIMIT STATE OF COMPOSITE BEAM WITH METAL-RIBBED DECK

SUBJECTED TO COMBINED INTERACTION OF AXIAL TENSION AND POSITIVE

BENDING

Ma. Bavan1, Shahrizan Bin Baharom

2, Siti Aminah Osman

3

1Department of Civil & Structural Engineering, National University of Malaysia, Malaysia.

Telephone: 0060133130643




Abstract

Axial tensile loads are often presented in the composite beams located in high rise buildings, cable stayed

bridges and inclined areas, and those are ignored in the prediction of ultimate limit state of composite beam

with metal-ribbed deck in the established design codes, which bring in conservative design. This research

studies had the hypothesis that the axial tension may accelerate the failure state of the composite beam with

unfavourable failure phenomenon. Three dimensional non-linear finite element method (FEM) model in the

composite beam with metal-ribbed deck subjected to flexure was developed and assessed with obtained

experimental results. Close agreement was observed in the moment-deflection responses and then, the

model was included to predict the ultimate strength of composite beam with metal-ribbed deck subjected to

combined axial tension and positive bending. It was found that the composite action significantly reduces

the ultimate strength of composite beam by excessive slip behaviour occur due to the axial tensile loads. The

material failure behaviours such as shear connection failure, concrete crushing and cracking, excess yielding

and buckling of steel beam and separation of deck are thoroughly analysed. In addition, the effects by

various levels of axial tension and reduction in ultimate strength are discussed. The effects of axial tension

in the shear stiffness and shear capacity due to weaker concrete by metal-ribbed deck are also verified.

Finally, the interaction diagram between axial and vertical loads at the ultimate limit state of composite

beam with metal-ribbed deck subjected to combined interaction of axial tension and positive bending is

proposed.

Keywords: Composite beam with metal-ribbed deck, Combined interaction of axial tension and positive

bending, Non-linear FEM analysis, Level of axial tension and ultimate strength deviation.



180

SECM/13/196

ENVIRONMENTAL MANAGEMENT PLAN TO IMPROVE THE WATER QUALITY OF

VAVUNIYA IRRIGATION TANK

S.S. Janen1, S. Pathmarajah

2

1Research and Facilitation, CIC Agri Business (Private) Limited, Sri Lanka

Telephone: +94 77 326 890 8

E-mail: [email protected], [email protected]

2Department of Agricultural Engineering, Faculty of Agriculture University of Peradeniya, Sri Lanka

Telephone: + 94 77 734 173 5


Abstract

Vavuniya Irrigation tank is located in the heart of Vavuniya city and provide livelihood assistance to both

farming and fishing communities. Due to its location, it has been adversely deteriorated by many human.

During the prolonged conflict, Vavuniya acted as front line for more than 15 years. Hence relocation of

IDPs was held and resulted unplanned infrastructure development, without aligning with the environment

mitigation measures. Identification of the source of pollution and categorize the source of pollution based

on industrial type to fabricate a feasible and efficient treatment system was the main intension of the study

and to identify the type of water weeds available and categorization of encroachments was undertaken to

the study the capacity reduction of the tank. Market, service stations, food industries are the main waste

generating source found and also Water storing capacity is progressively reducing due to sedimentation,

weed infestation and land encroachment. Household waste, rice mills, market, bakeries, food stores, fuel

stations, hotels, school, service station and bus stand are the main placed which direct waste water in to the

four identified drainage network. Houses, food stores, non government institutes, cultivation and retail shops

are newly build engorgement inside the tank area. Water hyacinth (Eichhornia crassipes), Salvenia (Salvinia

molesta), Jointweed (Polygonum barbatum) are the major weeds found in Vavuniya tank.

A system of centralized collection pond with aerators and skimming tanks for oil removal are recommended

for effective waste treatment system for Vavuniya tank and also Joint venture among Irrigation Department

and urban council will be highly appreciated during the future maintenance of the tank

Keywords: Source of pollution, Water storing capacity, Environment mitigation measures, Centralized

collection pond





181

SECM/13/197

BENEFITS OF STRUCTURAL WALL SYSTEMS IN MODERN CONSTRUCTION

1P.Kelly ,

2A.Emblin Snr.,

3P.Martins

Ritek – Building Solutions Pty Ltd,PO Box 730, Cooroy Qld, 4173, Australia

Telephone Number: +61-7-5472-2500 Fax: +61-7-5472-2500


Abstract

Residential building practices throughout the world have remained relatively unchanged throughout

the 19th and 20

th centuries with traditional masonry construction remaining the preferred building

method across many countries. Many countries are demanding greater productivity and efficiency in

their building and construction sector as a way to drive economic growth. Additionally, many

countries are facing increased costs of construction including higher labour costs, higher equipment

costs as well as shortage of qualified labour and pressure to build in a more environmentally friendly

manner, a new way of systemised building is required to achieve the benefits of masonry construction

without experiencing the major problems and waste associated with this traditional form of

construction. This paper will outline new building methodologies around the world, and in particular

Australia, that can provide benefits in most countries around the world, and certainly in Sri Lanka,

with respect to generating greater efficiencies and productivity in building leading to an increase in

the quality of building construction; and assisting in the completion of projects on time without

having to use additional labour/materials or incur additional costs.

Keywords: Building productivity, building system, modular construction, masonry construction

182

SECM/13/198

CORROSION RESISTANT REINFORCEMENT FOR SUSTAINABLE BRIDGES AND

UNDERGROUND STRUCTURES

G. Tharmarajah1, P. Archbold

2 , S.E.Taylor

3

1Faculty of Engineering, Sri Lanka Institute of Information Technology, Sri Lanka.

Telephone: +94 112 413 900 (ext. 6007)


2School of Engineering, Athlone Institute of Technology, Republic of Ireland.

Telephone: +353 906 442 552


3School of Planning, Architecture and Civil Engineering, Queen‟s University Belfast,

United Kingdom.

Telephone: +44 (0)28 9097 4010


Abstract

Bridge decks and underground service structures are often exposed to extreme environmental

conditions where structural damage due to corrosion is a common phenomenon. This results in

reduced service life and expensive repairs. Fibre Reinforced Polymer (FRP) products such as

reinforcing rods offer a potential viable alternative to the steel reinforcement, which would allow

better service life for structures and much reduced concrete cover as theses bars require minimal

environmental protection. Higher service life and reduced quantities of concrete used in FRP

reinforced concrete structures can be an attractive feature in terms of sustainability.

Carbon FRP (CFRP), Basalt FRP (BFRP) and Glass FRP (GFRP) are the popular corrosion resistant

bars which can be used to replace steel to produce more sustainable structures. A case study of two

researches is discussed in this paper where GFRP and BFRP were used to replace the steel

reinforcement without compromising strength and service behaviour of the structures. A comparison

between the behaviour of steel reinforced structures with similar FRP reinforced structures and the

advantages of building sustainable infrastructure using corrosion resistant reinforcement is also

discussed in this paper.

Keywords: Corrosion, FRP, steel, sustainability, concrete structures



183

SECM/13/200

ADOPTION OF EURO CODES FOR COMMONLY USED BRIDGE DECK TYPES OF SRI

LANKA

S Seyanthan 1, M.T.R. Jayasinghe

2




Abstract

The design engineers in Sri Lanka have used standards based on British practice for nearly a century.

However, with the adoption of Euro Codes as the main standard by the United Kingdom, there is a

need for adopting the Euro Codes with the relevant national annextures for Sri Lankan highway sector

with special reference to the bridges. This paper describes some important findings that would be of

high significance for the bridge engineers in their change over to Euro codes. This deep study covers

many types of decks that have been used in Sri Lanka and also the probable ones that can be adopted

in future.

184

SECM/13/201

USE OF HIGHER GRADE CONCRETES TO OPTIMIZE BRIDGE DECKS

U N L Sampath 1, M.T.R. Jayasinghe

2

1G Ramanan, Department of Civil Engineering, University of Moratuwa

2M.T.R. Jayasinghe, Department of Civil Engineering, University of Moratuwa


Abstract

With the latest advances in concrete technology and also the introduction of high range water

reducing admixtures and other latest developments leading to self compacting concrete, it is possible

to achieve strengths in the range of Grades 60 and 70. Such high strengths will allow a greater stress

range than possible with Grades 30 and 40 as traditionally used. Thus, by using the same standard

section, there is a very good possibility for optimizing the bridge decks. This paper describes such

finding of a deep study undertaken from the point of view of improving the sustainability of highway

bridges.

185

SECM/13/202

BEHAVIOUR OF THE COMPOSITE BEAM WITH WEB OPENINGS SUBJECTED TO

COMBINED INTERACTION OF FLEXURE AND TORSION

Ma Bavan1, Shahrizan Bin Baharom

2, Siti Aminah Osman

3


Telephone: 0060133130643




Abstract

This paper presents the structural performance of the composite beam with web openings subjected to

combined interaction of flexure and torsion. A three dimensional finite element model (FEM) with the

material components in nonlinear behaviours was developed for a composite beam. The FE model was then

included for a specific interaction relationship in flexural-torsional moments, and the ultimate strength of

flexural moment with torsional moment was verified with available experimental results. The FE model was

in very good agreement with the responses of experiment in the stiffness and ultimate flexural moment

capacity. The square openings with various widths were subsequently employed in the structural steel beam

of FE model, and the ultimate flexural moment capacity was predicted with applying same torsional

moment. The significant reduction was observed in the ultimate flexural moment and stiffness with the

comparison of the FE model without openings. The material fractural behaviours of the composite beam

due to web openings are thoroughly discussed in this paper. Finally, the flexure-torsion interaction

relationship of the composite beam with web openings is presented in results.

Keywords: Composite beam with web openings, Combined interaction of flexure and torsion, Non-linear

FEM analysis, Ultimate strength of flexural and torsional moments.



186

SECM/13/203

STRUCTURAL ANALYSIS OF AERODYNAMICALLY SHAPED LIGHT WEIGHT

HOVERCRAFT

S. Raja1,D.Dwarakanathan

2, D.K.Kulkarni

3,Umesh B.C.

4

1Scientist Dynamics & Adaptive Structures Group STTD, CSIR-NAL

2 Scientist Dynamics & Adaptive Structures Group STTD, CSIR-NAL

3Department of Civil Engineering, SDMCET, Dharwad-580002

4SDMCET, Dharwad-580002


Abstract

A hovercraft is a vehicle supported on a cushion of air supplied by a powered fan mounted on the

craft. Hence, this vehicle or craft can travel over land or water, with cushion of air as its wheels. The

hovercraft was invented by Christopher Cockerell in 1956. The theory behind one of the most

successful inventions of the 20th century, the Hovercraft, was originally tested in 1955 using an

empty KiteKat cat food tin inside a coffee tin, an industrial air blower and a pair of kitchen scales. Sir

Christopher Cockerell developed the first practical hovercraft designs; these led to the first hovercraft

to be produced commercially, the SRN1.

Christopher Cockerell's idea was to build a vehicle that would move over the water's surface, floating

on a layer of air. This would reduce friction between the water and vehicle. To test his hypothesis, he

put one a smaller CAN inside a larger CAN and used a hairdryer to blow air into them. The

downward thrust produced was greater when one CAN was inside the other rather than air just being

blown into one CAN.

In this project, an attempt is made to design such a vehicle. The first task was to choose an appropriate

aerodynamic configuration to reduce drag coefficient. In the second task, the weight of the vehicle is

optimized using light weight composite material. Static and dynamic analyses are carried out to

qualify the vehicle design. Further, interaction of the structure with fluid is studied to understand the

coupling effect between the structure and fluid and its effect on the structural frequency.

Keywords: Modeling tools Catia V5, Hypermesh v11, Analysis tools MSC NASTRAN

187

SECM/13/205

ELECTRICAL AND OPTICAL STUDIES ON PAN-LIBF4 BASED GEL POLYMER

ELECTROLYTES

K. V. L. Amarasinghe1, V. A. Seneviratne

2, L. R. A. K. Bandara

3, M. A. K. L. Dissanayake

4

1Postgraduate Institute of science, University of Peradeniya, Sri Lanka.



2Department of Physics, Faculty of Science, University of Peradeniya, Sri Lanka.

Telephone: +94778472345


3Department of Physics, Faculty of Science, University of Peradeniya, Sri Lanka.

Telephone: +94777619271


4Institute of Fundamental Studies, Kandy, Sri Lanka.

Telephone: +94 777 130667


Abstract

The Gel Polymer Electrolytes (GPEs) are promising materials for the ever-growing need for high

energy density power sources such as lithium ion batteries. The emphasis of this work is on a

plasticized polyacrylonitrile (PAN) and lithium tetrafluoroborate (LiBF4) based GPE system with and

without ceramic filler titania (TiO2). The GPEs have prepared as follows. Eighty percent of the GPEs

consist of EC and PC at a ratio of 1:1 (40% each). The remaining 20% of the sample consists of

different percentages of polymer and salt. The ionic conductivities of all samples with different

polymer to salt ratio are in the order of ~ 10-3

S cm-1

at room temperature.

FT-IR studies were carried out to investigate the interactions of Li+ ions with PAN and the

plasticizers. Many vibrational frequency modes have been identified to verify the interactions of Li+

ions with the plasticizers (EC and PC), which are mainly occurring with the oxygen atoms of the ring

group of plasticizers (including both C=O and C-O bonds).

The filler addition has given a mechanical stability to the GPEs without a significant reduction of the

ionic conductivity. The high ionic conductivities suggest that these are good candidates for lithium ion

battery applications.

Keywords: Polyacrylonitrile, Gel polymer electrolytes, Filler effect, Plasticizers, FT-IR spectroscopy






188

SECM/13/206

LONG TERM EFFECT OF CaCl2 SOLUTION ON HYDRAULIC CONDUCTIVITY OF

EXPANSIVE CLAYS AND EXPANSIVE CLAY-BENTONITE MIXTURES

J.A.D.K.Wanigarathna1, S.Arooran

2, R.Gobirahavan

3,L.C.Kurukulasuriya

4, K.Kawamoto

5


Telephone: +94-077-6975911



Telephone: +94-077-9361512



Telephone: +94-077-7147916



Telephone: +94-81-2393514



Telephone: +81-48-858-3572


Abstract

The objective of this study was to investigate the long-term effects of CaCl2 solution contact on

hydraulic conductivity of consolidated expansive soil. For this purpose an expansive soil was obtained

from Moragahakanda area (Soil M) situated in the central wet zone of Sri Lanka and the same soil

was mixed with 5% and 10% bentonite (Soil M+5% and Soil M+10%) as possible candidate materials

for use in a liner for municipal landfills. De-aired water and 1M CaCl2 solution to represent divalent

compounds present in leachate generated in a liner were used as permeant liquids in hydraulic

conductivity tests. To evaluate the effect on long-term hydraulic conductivity, consolidated soil

samples were subjected to constant head permeability tests until the total accumulated flow through

the samples exceeded 20 times of initial pore volume (PVF) to subject for long term effects. Under the

permeation of de-aired water the hydraulic conductivity of the expansive soil samples consolidated under a

pressure of 50 kPa, decreased from 5 x 10-8 cm/s to 0.87 x 10

-8 cm/s with the increase of percentage of

bentonite up to 10%. While conducting long term tests under permeation of 1M CaCl2, it was observed that

the hydraulic conductivity varies with PVF. However, after the permeation for 20 PVF, almost steady

hydraulic conductivity values were observed for all tested soils. Under the permeation of CaCl2, the

hydraulic conductivity decreased from 5.12 x 10-8 cm/s to 2.25 x 10

-8 cm/s with the increase of percentage of

bentonite up to 10%. The soil consolidated under a pressure of 184 kPa exhibited the lowest hydraulic

conductivity under permeation of 1M CaCl2. When the hydraulic conductivity values of candidate soils

under permeation of de-aired water and 1M CaCl2 solution were compared, it can be seen that the

increase of hydraulic conductivity under permeation of 1M CaCl2 is not significant, except for Soil M

and Soil M+5% consolidated under 46 kPa pressure. As compared with the recommended hydraulic

conductivity for Compacted Clay Liners (i.e.1x10-7cm/s), all the candidate soils exhibited sufficiently

lower values of hydraulic conductivity except for Soil M and Soil M+5% consolidated under 46 kPa.

However, since bentonite mixed expansive soils exhibited much lower hydraulic conductivity than

that of unamended soil, it is more suitable for the construction of base liners in municipal landfills.

Keywords: Expansive soil, Bentonite, CaCl2 solution, Hydraulic Conductivity






189

SECM/13/207

INVESTIGATION ON MAINTENANCE CHALLENGES OF A COAL POWER PLANT

BASED ON EFFICIENCY AND BEARING PERFORMANCE ANALYSIS

S.Sobikha1, N.Arunprakash

2, S.Sasikumar

3

1Department of Mechanical Engineering, University of Peradeniya, Peradeniya, Sri Lanka.

E-mails:[email protected]

2Department of Mechanical Engineering, University of Peradeniya, Peradeniya, Sri Lanka.

E-mails: [email protected]

3Consulting Engineers and Contractors Pvt Ltd (CEC), Colombo-08, Sri Lanka


Abstract

In this work we investigate the bearing failure and the overall efficiency of a 300MW power plant.

We found that the actual efficiency was 10% less than the theoretically expected values. We then

investigated the possible reasons for those efficiency variations and found that it was due to the

significant amount of changes in the viscosities at the bearings.

Investigation of the bearing temperature showed significant temperature variations between

theoretical and actual readings. We found that as a result the bearing lubricants failed and was the

primary cause for the bearing failures of the plant. We conducted a viscosity analysis and bearing

performance analysis based on three types of lube oils as Servo-prime-32, 46 & 100 specified by

Indian Oil Corporation limited for the steam turbines. Viscosities of oils were calculated for each six

bearing‟s temperatures and film thickness of oils were calculated at each bearing positions and were

compared with minimum standard film thickness. According to this study Servo-prime-46 was

selected to be the most suitable for plant‟s purpose.

Keywords: Plant efficiency, Oil film thickness, Bearing Performance, Viscosity analysis, Lube oil




190

SECM/13/208

SOLUTION GROWN CdS AS A WINDOW LAYER FOR SOLAR CELL APPLICATIONS

W.G.C. Kumarage1, K.I.H. Senevirathne

2, V.A. Seneviratne

3,C.P. Jayalath

4, B.S. Dassanayake

5

1Department of Physics, University of Peradeniya, Peradeniya, Sri Lanka.

Telephone: +94812394580; Fax: +94812388018



Telephone: +94812394580; Fax: +94812388018



Telephone: +94812394606; Fax: +94812388018



Telephone: +94812394602; Fax: +94812388018



Telephone: +94812394587; Fax: +94812388018


Abstract

Synthesis of CdS thin films was carried out using Chemical Bath Deposition (CBD) to be applied as

the window layer of inorganic CdS/CdTe solar cells. CdS was grown using cadmium sulfate, thiourea,

ammonia and ammonium hydroxide on commercially available glass slides. Properties of the films

were optimized by varying the solution parameters such as chemical concentrations and bath

temperature. Furthermore the effect of substrate rotation on CdS deposition was compared with a

horizontal stationary substrate and a substrate placed at 45˚ angle in the same bath.

UV-visible spectroscopy data revealed that optical transmittance of the rotated film is lower than the

stationary samples. The band gap calculations yielded almost similar values for both rotated and

stationary deposited films within the experimental uncertainties. Transmittance in the range 300 – 800

nm was found to decrease with increasing NH3 volume for both stationary and rotated samples. When

films fabricated at bath temperatures from 40 to 80 ˚C were studied for their optical and electrical

properties, it was revealed that optical band gaps and fractional thicknesses increase when moving

away from the bath temperature range of 50 – 60 ˚C, potentially due to different CdS deposition

mechanisms at higher and lower temperatures.

Keywords: CdS, inorganic solar cells, chemical bath deposition, UV-Visible, XRD











191

SECM/13/209

EFFECTS OF CaCl2 SOLUTION ON PHYSICAL, INDEX AND CHEMICAL PROPERTIES

OF EXPANSIVE CLAY LINER MATERIALS

R.Gobirahavan1, S.Arooran

2, L.C.Kurukulasuriya

3, J.A.D.K.Wanigarathna

4, K.Kawamoto

5


Telephone: +94-077-7147916



Telephone: +94-077-9361512



Telephone: +94-81-2393514



Telephone: +94-077-6975911



Telephone: +81-48-858-3572


Abstract

The main task of clay liners in landfills is to mitigate the migration of pollutants to the groundwater sources.

These clay liners are exposed to various types of chemical, physical and biological processes due to contact

with leachate. Leachate includes different types of inorganic and organic compounds which affect

thephysical, index and chemical properties of clay liners that can affect the long-term performance of these

clay liners as a barrier. The CaCl2solution exerts the strongest effect on clay liner materials than any other

chemical in leachate.

The objective of this study was to evaluate the effect of inorganic salt CaCl2 on some physical, index and

chemical properties of expansive soil obtained from Moragahakanda area (Soil M) situated in the central

wet zone of Sri Lanka. Also, the effect of CaCl2 onSoil M amended by 5% (Soil M+5%) and 10%

(Soil M+10%) bentonite, on the selected physical, index and chemical properties was investigated. The

effect on physical, index and chemical properties was investigated by carrying out Atterberg Limits Tests,

Modified Free Swell Index, Specific Gravity, Shrinkage Limit, Mechanical Analysis, pH and Electric

Conductivity before and after samples consolidated under pressures of 50, 100, and 200 kPa were subjected

to the permeation of 1M CaCl2 solution under gradually increasing constant head of 50, 100 and 150 kPa,

up to replacement of their void volumes by as much as 20 times to simulate long term contact.

After long term contact of consolidated soil samples with CaCl2 solution, the liquid limit value of Soil M,

Soil M+5% and Soil M+10% is found to be decreased by 22%, 19% and 31% respectively, but only the

plastic limit value of Soil M+10% was increased by 12% points and also the Specific Gravity and Modified

Free Swell Index are decreased with the increase of percentage of bentonite up to 10% and the chemical

properties such as pH and Electric Conductivity are also decreased. Although the LL and PI values were

reducedafter contact with CaCl2solution, the soil classification of Soil M (CH) and Soil M+5% (CH)

remained same. However, Soil M+10% was reclassified asClay of High Plasticity (CH) from its initial

classification of Clay of Very High Plasticity (CV).

Keywords: Clay liners, Expansive soil, Bentonite, CaCl2 solution, Physical, Index and Chemical properties






192

SECM/13/210

DISSOLVED OXYGEN CONCENTRATION VARIATION IN THE MEDA ELA CANAL IN

KANDY DUE TO URBANIZATION: A CASE STUDY

A.C.S.Perera

Postgraduate Institute of Agriculture, University of Peradeniya, Sri Lanka.



Abstract

Meda Ela is a natural water stream starting from Kandy Lake at the center of Kandy and runs across

the city to the southern boundary. Waste water from industries, garages, laundry community, hospital,

bus stand and residences that expanded with urbanization is released into this stream depleting its

natural beauty and making it a waste channel over time. The objective of this study was to investigate

the Dissolved Oxygen (DO) concentration variation along the Meda Ela canal, determine the key

areas where DO concentration is low, identify the pollutant sources and time of the day when DO is

lower.Water samples were obtained in morning and afternoon at eight different sampling points along

the stream line starting from the Kandy Lake to the outlet of the canal where it merges with the

Mahaweli River, to estimate DO concentration. Dissolved oxygen in the Meda Ela was lower in the

mid-day when the industries are most active and where industries and residences are located. These

results suggest that DO is reduced by industrial and domestic activities in the catchment area. Steps

should be taken to prevent polluting this natural water body before it loses its natural recovery ability

permanently.

Keywords: Kandy Meda Ela, Dissolved oxygen, Industries, Urban activities


193

SECM/13/211

DESIGN OF A HOVERCRAFT

S.Tharani1 , A.Chenduran

2

1Department of Mechanical Engineering, University of Peradeniya, Sri Lanka.

Telephone: +94771616297



Telephone: +94775397748


Abstract

The Hovercraft is a modern invention is known as AVC. It is capable of traveling over land, water,

mud, land and ice. And it‟s using for transports, civilian and military applications and transports in

hostile environments. The type of the hovercraft is twin engine. ACVs require two engines: one for

the lift the vehicle up (hovering action), and the other for forward thrust.

The concept of an AVC was originally proposed in 1716 by Emanuel Swedenborg. The modern

hovercraft was invented by British inventor Christopher Cockerell in 1955. Cockerell is improving his

design from the aspect of reducing the wave and frictional resistances encountered by a craft moving

in water. He struck upon the idea of using air as a lubricant, which would separate the hull of the craft

from water. To reduce the wave resistance one must increases and vice-versa. Most normal designs

are a compromise between the two. He imagined that if he could introduce a film of air between the

hull and water, skin friction would be negligible and be free to design entirely around the problem of

wave resistance.

This paper presents the Design of a hovercraft for one passenger.The size of the hovercraft is 10 ft. It

can carry nearly 200 kg and the Speed of Vehicle is depending on the type of the engine. The type of

the skirt is finger skirt because it‟s most frictionless and can able to get the most hover-height.

Keywords: Air cushion vehicle (ACV),hull, lubricant.





194

SECM/13/212

SHEAR CAPACITYOF LIPPED CHANNEL BEAMS WITH WEB OPENINGS – DESIGN

RULES AND IMPROVEMENTS

Poologanathan Keerthan1, Mahen Mahendran

2

1Science and Engineering Faculty,Queensland University of Technology, Brisbane, QLD 4000,

Australia


2Science and Engineering Faculty,Queensland University of Technology, Brisbane, QLD

4000, Australia


Abstract

Cold-formed steel Lipped Channel Beams (LCB) with web openings are commonly used as floor joists

and bearers in building structures. The shear behaviour of these beams is more complicated and their

shear capacities are considerably reduced by the presence of web openings. Hence detailed numerical

and experimental studies of simply supported LCBs under a mid-span load with aspect ratios of 1.0

and 1.5 were undertaken to investigate the shear behaviour and strength of LCBs with web openings.

Experimental and numerical results showed that the current design rules in cold-formed steel structures

design codes are very conservative. Improved design equations were therefore proposed for the shear

strength of LCBs with web openings based on both experimental and numerical results. This research

showed a significant reduction in shear capacities of LCBs when large web openings are included for

the purpose of locating building services.A cost effective method of eliminating such detrimental

effects of large circular web openingswas also therefore investigated using experimental and numerical

studies. For this purpose LCBS were reinforced using plate, stud, transverse and sleeve stiffeners with

varying sizes and thicknesses that were welded or screw-fastened to the web of LCBs. These studies

showed that plate stiffeners were the most suitable. Suitable screw-fastened plate stiffener

arrangementswith optimum thicknesses werethen proposed for LCBs with web openingsto restore their

original shear capacity.This paper presents the details of finite element analysesand experimentsof

LCBs with web openings in shear, and the development of improved shear design rules. It then

describes the study to determine the optimum plate stiffener arrangements and the results. The

proposed shear design rules in this paper can be considered for inclusion in the future versions of cold-

formed steel design codes.

Keywords:Lipped Channel Beams, Web openings, Finite element analysis, Shear Tests, Shear

capacity, Plate stiffener, Screw-fastening, Cold-formed steel structures



195

SECM/13/213

DESIGN OF LIGHT GAUGE STEEL ROOFING SYSTEMS SUBJECT TO HIGH WIND

FORCES

Mayooran Sivapathasundaram1 , Mahen Mahendran

2

1Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000,

Australia


2Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000,

Australia


Abstract

Light gauge steel roofing systems made of thin profiled roof sheeting and battens are used commonly

in residential, industrial and commercial buildings. Their critical design load combination is that due to

wind uplift forces that occur during high wind events such as thunderstorms and tropical cyclones.

However, premature local failures at their screw connections have been a concern for many decades

since cyclone Tracy devastated Darwin in 1974. Extensive research that followed cyclone Tracy on the

pull-through and pull-out failures of roof sheeting to batten connections has significantly improved the

safety of roof sheeting. However, this has made the batten to rafter/truss connection the weakest, and

recent wind damage investigations have shown the failures of these connections and the resulting loss

of entire roof structures. Therefore an experimental research program using both small scale and full

scale air-box tests is currently under way to investigate the pull-through failures of thin-walled steel

battens under high wind uplift forces. Tests have shown the occurrence of pull-through failures in the

bottom flanges of steel battens and the need to develop a simple test method to investigate this failure

as a function of many critical parameters such as steel batten geometry, thickness and grade, screw

fastener sizes and screw head underside details, screw tightening, and so on. This paper presents the

details of the local failures that occur in light gauge roofing systems, a review of the current design and

test methods for steel battens and associated shortcomings, and the test results obtained to date on the

pull-through failures of battens from small scale and full scale tests. Finally it proposes the use of

suitable small scale test methods that can be used by both researchers and manufacturers of such

screw-fastened light gauge steel batten systems.

Keywords: Cold-formed steel structures, Light gauge steel roofing systems, Steel battens, Wind uplift

forces, Pull-through failures, Test methods.



196

SECM/13/214

EVALUATION OF EXISTING BUILDINGS THROUGH THE PASSIVE SEISMIC

TECHNIQUE

P.Cicchiello1

1Department of Structural Engineering, Cicchiello Integrated Engineering, Italy.

Telephone: +39 039.9466428; Fax: +39 039.9461.233 website: www.cicchiello.it


Abstract

Among existing buildings, most part of the technical efforts are oriented to obtaining the actual evaluation

of the dynamical properties, in order to guide the initial phases of the design process.

The recently introduced Italian Building Code, namely NTC2008, have changed seismic performances

requested from new buildings. A relevant part of the existing structures has been built without taking into

account the event of an earthquake.

Many of the existing buildings are not able to properly effort an earthquake, thus implicating that they are to

be evaluated and, for sure, retrofit in order almost to reduce their seismic vulnerability.

This paper aims to present the guide-lines of a simple method oriented in this direction. It's main scope is to

determine the dynamical properties of an existing building, which is based on the use of the passive seismic

energy as the sourcefor studying the actual behavior of a structure subjected to non-static actions.

After having shortly presented the theoretical aspects of the technique of the passive seismic, it will be

presented the practical application of the proposed method to two existing buildings.

Keywords: seismic retrofit, passive seismic, existing building, dynamical properties


197

SECM/13/215

RESPONSE OF THE SUDANESE CONSTRUCTION INDUSTRY TO GLOBALIZATION: A

COMPREHENSIVE REVIEW TO THE CHALLENGES AND POSSIBLE OPPORTUNITIES

S.Y.M. Mahmoud1, E.A.M Elshiekh

2

1Department of Civil Engineering, University of Science and Technology, Sudan.

Telephone: +249121836649


2Department of Construction Engineering, Sudan University of Science and Technology, Sudan

Telephone: +249912198376


Abstract

“Globalization” is a term that has been given several definitions by different commentators. Many

theories and models were presented in the relevant literature in a trial to explain the process of

globalization. Some described globalization as a process that embraces growing interdependence

between national economies resulting in a trend towards global markets, global production and global

competition. Others have argued that the concept of globalization evolved partly due to the trend for

increasing international trade across national boundaries and the conduct of business activities in more

than one country.

Construction, as one of the major sectors contributing to nations‟ economies, is undeniably affected

by globalization. As a phenomenon, it has posed changes in the labor relationships, industrial

structure and the industry competitiveness. The construction industry in Sudan, being similar to its

corresponding industries in many small developing economies, is expected to struggle when it deals

with these issues while trying to pursue a sustainable development.

The main objective of this paper is to review globalization in its wider context and reflect on major

issues facing today's global construction industry with special focus on the case of the Sudanese

construction industry. In that sense, the presented study explores how the Sudanese construction is

responding to the changing construction business environment and attests the challenges and possible

opportunities. Moreover, the study attempts to measure the extent to which the industry and its

participants are coping with this increasing global competition in terms of new approaches for design,

construction, operation, and maintenance.

The study devices an industry-wide survey with all the stakeholders participating to elicit information

on the issues raised. Consulting engineers, contractors, designers, academics and researchers will be

asked to give an account on how they respond to the rapidly increasing pace of technological

advances, the expected shrinking in the construction workforce, declining productivity and increasing

global competition. The survey outcomes highlight the necessary actions for the transformation of the

Sudanese construction industry in response to globalization. The study recommends a rethinking in

the current understanding of how industry participants in Sudan do the work considering their

organizations as global firms operating in a new and widely open market.

Keywords: globalization, construction industry, Sudan, industrial structure


198

SECM/13/217

CONTAINMENT DESIGN TO FLOODING IN AN URBAN ENVIRONMENT

1Xiaohua Wei,

2Soon Keat Tan

1Maritime Research Centre, Nanyang Technological University,50 Nanyang Avenue, 639798

Singapore

Telephone: +65 91058180


2Maritime Research Centre, Nanyang Technological University,50 Nanyang Avenue, 639798

Singapore

Telephone: +65 67905321


Abstract

Singapore is situated nearthe Equator and heavy tropical rainstorms are common occurrences. The

average annual rainfall is about 2400 mm. Heavy rainfall is generally observed from November to

January (ranging from 240 to 345 mm/month), and rainfall in other months is approximately evenly

distributed at about 150 mm/month. The wetter periods are more concentrated and there are more

pronounced dry periods in the annual rainfall distribution throughout the year.Flash flood events

sometimes take place in the garden city during high rainfall season.This paperpresentsa new concept

for urban flood managementwhen the drainage system is overwhelmed. Generally the amount of

runoff that could not be accommodated by the drainage system would over flow from the drainage

channel and flow overland. The overland flowtypically follows the path of the least resistance to local

low areas. It follows thatan open area in the low ground wouldform a natural flood receptacle and a

storage tank could be designed and installedunderground in this flood receptacle area. This storage

tank then serves as a detention pond connected to the conventional drainage system when there is

imminent threat flood.The storage tank needs only cater to the amount of excessive runoff over the

drainage capacity. In this design approach, empirical synthetic unit hydrograph for urban watersheds

are used to establish direct runoff hydrographs from given rainfall excess hyetographs. Examples base

on cases of different rainfall return years in Singapore (5-year, 10-year and 25-year) are presented.

By using the relationship of rainfall~runoff established in this study, the relationship of Rainfall

duration~Exceedancetime~Storage volumeisobtained. This relationship can be a reference for the

design of storage tank.

Keywords: Rainfall, Excess runoff, Urban flood, Detention pond

199

SECM/13/218

IMPROPER SEPTAGE DISPOSAL AND ITSIMPACT ON SURFACE AND

GROUNDWATER IN SRI LANKA

S. Fernando1, N. Jayathilake

2, P. Drechsel

3, C.Semasinghe

4

International Water Management Institute

127, Sunil Mawatha, Pelawatte, Battaramulla, Sri Lanka

Telephone: +94 11 2880000; Fax: +94 11 2786854


2, [email protected]

3,

[email protected]

Abstract

A field study was conducted as a part of the septage management study in Sri Lanka covering 41

Local Authoritiesacross the country to identify the scale and significance of pollution via present

septage*disposal practices on surface and groundwater resources. Households in currently 59% of all

335 Local Authorities (LAs) in Sri Lanka, have access to septage collection services. Nearly every

third LA (29%) has its own septic truck while other LAs either hire septic trucks from neighbouring

LAs or in 6% of the cases from the private sector.

All service providers together collect about 31% of the produced septage; 13% is treated, while 78%

is either dumped in landfills, depressions, water ways or other places (for example LAs near Colombo

dump their septage into the metropolitan sewer system and ocean outfall). The wild dumping practice

poses a significant risk which might not only undermine the health and environmental benefits

expected from „improved toilet facilities‟ but also „safe drinking supply‟.

As in most low income countries, Sri Lanka too is lacking sufficient field data to assess the scale of

pollution from theseimproper disposal practices.While long term monitoring would be ideal to

understand the consequences of this practice on environmental quality, food safety and health, the

informality of the practice and resources needed make this a challenging task, and might only defer

authorities from taking action. Under this study it was attempted to establish a risk ranking system to

assess therisk of pollutionon the water resources from septage, while compiling a set of carefully

selected proxy indicators through a comprehensive field study without resorting any laboratory

testing. This risk ranking system allowsvisualizing the significance of the risk graphically across cities

and different disposal practices. The developed risk ranking system is open to further refinements and

can then be used either as a rapid pollution assessment tool or as a site screening method prior tocarry

out a detailed field study.

*The term septagerefers here to excreta or faecal sludge collected from onsite sanitation systems

such as pit latrines, septic tanks, etc.

Keywords: Risk ranking system, Septage, Indicators, Pollution, Water resources





200

SECM/13/219

PERFORMANCE OF A CONSTRUCTED WET LAND TO TREAT WASTE WATER FROM

TODDY DISTILLERY UNIT

V Bama1, M Thushyanthy

2,P Alvappillai

3, M Pirabhaharan

4

1Deptartment of Agricultural Engineering, Faculty of Agriculture, University of Jaffna, Sri Lanka



Abstract

Effluent „Coda‟ originating from palmyrah toddy distillery units is the major source of environmental

pollution in the Jaffna district of Sri Lanka. Spent wash produced from distilleries is rich in organic

material and characteristically less toxic. The study was aimed to assess the potentiality of constructed

wetlands for treating of distillery spent wash in lab scale with various configurations treatments,

before discharge to the land. Effluent was collected from Thikkam distillery in Jaffna directly from

the out let unit without accumulating in aerobic tank. The effluent was diluted as 5, 4, 3, 2, and 1

times with groundwater. Treatments were discarded due to complete failure. Observations were

considered for the failure of the plants. As improvement, the effluent was aerated with an air

compressor and the pH value was adjusted to 6 using CaCO3. Further effluent was diluted 5, 10 and

20 times to facilitate the optimum plant growth. The aquatic plants, Eichhormia sp, Lemna sp, Pistia

sp and Lemna minor sp were selected. Constructed wet land was designed and fabricated in lab scale.

Initial parameters of the effluent were measured. Samples from inlet and outlet of the artificial

wetland were collected on two days interval for one week and analyzed for pH, BOD, COD,

Turbidity, NO3-, PO43-, TDS, and EC using standard methods with replicates with hydraulic

retention time of 2, 4, and 6 days. Even diluted by five times were often above the permissible

standards specified by the Central Environmental Authority for the discharge of industrial effluents

into land. The aquatic plants Eichhormia sp, Lemna sp, Pistia sp and Lemna minor were used

successfully to treat the spent wash, after aeration, pH adjustment with dilution factor of 10. Proper

dimensions of the constructed wet land was reduced the dilution from ten to five. Complete death of

Pistia was observed in dilution of five. Constructed wetlands were successfully removed TDS, nitrate,

phosphorus, BOD, COD, turbidity, EC, and change the pH. The maximum removal rates of EC, TDS,

COD, BOD, nitrate, and phosphate in constructed wetland were 50.14%, 48.42%, 45.5%, 56.3%,

35.3%, and 54% respectively. It was found constructed wetland shows highly significant removal

efficiency of all tested components by Lemna minor . The hydraulic retention time of six days was

showed the highest removal efficiency and maximum reduction rate of all the tested components. But

hydraulic retention time of four days which is more possibility to keep, because the values of

constituents of distillery waste are moreover reached the permissible standards specified by the CEA

to discharge to land or irrigation. After treated effluent through, construction of wetlands could be use

as a liquid fertilizer for cultivating field .

Keywords: Distillery effluent, Constructed wetland, Dilution factor, hydraulic retention time,

Removal efficiency

201

SECM/13/220

DESIGNING PILED BRIDGE ABUTMENTS FOR A GRADE SEPARATED

CROSSINGUSING TOP DOWN CONSTRUCTION

1Loranjana Jayawardena,

2Stephen Xu

1CivilStructures &Bridges Service Group,GHD Pty Ltd, Sydney, Australia.

Telephone: +61459813548; Fax: +61292397199


2CivilStructures &Bridges Service Group,GHD Pty Ltd, Sydney, Australia.

Telephone: +6128898 8878; Fax: +61292397199


Abstract

Grade separated bridges are required in highway crossings where one road goes under an existing

road. Large diameter cast-in-situ piles acting as a cantilevered wall are frequently used in the

construction of permanent retaining walls and abutments in these bridges. For deeper excavations,

supplementary ground anchors are provided. These methods generally provide an economic solution

as they avoid excessive bulk excavation and facilitate top down construction.

Since bridge abutments and wing walls are usually designed as unconnected structures, there is scope

in reducing substructure pile foundation requirements by structurally integrating them with a

continuous capping beam, which will be referred to in this paper as an “Integrated Piled Wing wall

Abutment”. The design of an Integrated Piled Wing wall Abutment requires three-dimensional

structural analysis.

This paper describes the design process for the Integrated Piled Wing wall Abutment in accordance

with the Australian Standard for Bridge Design. It will also compare the advantages offered by this

unique structural system when compared to other piled wall alternatives that could be used in top

down construction.

Keywords: Abutment, Pile, Wing wall, Top-down construction, Soil–structure interaction

202

SECM/13/221

PROJECT MANAGEMENT: OVERVIEW OF GENERAL CONCEPTS

A. Sangha

Center of Excellence on Sustainable Development in the Context of Climate Change

Asian Institute of Technology,Thailand.

Telephone: +6625245552


Abstract

Project management is an essential tool used to plan, organize, execute and utilize the available

resources in order to achieve specific goals and targets. Human resource is the most important asset of

project management in pursuit to accomplish the desired results (outputs, outcomes and impacts).

Innovation and management of sudden changes efficiently are set of skills expected by international

organizations from its human resource. Efficiency, quality of tasks performed and management of

budget are primary challenges in the project management.

The primary target of project management is to complete the project goals and objectives in time,

keeping in mind unseen challenges during the entire project phase. Secondary target of project

management is to optimize the allocated inputs to achieve the pre-defined objectives. Tertiary target

of project management is to monitor and evaluate the project results against the pre-defined allocated

inputs. Project management comprises of four main phases namely, project initiation, project planning

and design, project execution and project reporting (activities, financial, monitor & evaluate and

outputs & outcomes).

Keywords: project management, monitor, target, time.




203

SECM/13/222

EVALUATION OF THE DIFFERENT FILTER MEDIAS FOR THE TREATMENT OF THE

PADDY SOAKED WASTEWATER

S. Gobika1, M. Thusyanthi

2, P. Alvaipillai

3, M. Prabaharan

4, N. Kannan

5

1Department of Agricultural Engineering, Faculty of Agriculture, University of Jaffna



Abstract

Paddy is the most important food crop in Sri Lanka. Raw rice processing and parboiling are the paddy

processing methods are practiced in Sri Lanka. Soaking is the one of the step of the parboiling it

consumes considerable amount of water out of which small fraction is consumed by paddy grains and

rest is left as effluent. In Jaffna, milling units are discharged the effluent in open dumping method.

The effluent contain large amount of organic compounds but, doesn‟t contain toxic compounds. But

this continuous discharge cause adverse environmental effect. The stagnant water emits odours due to

the fermentation. There are no efficient technologies to treat the effluent before discharging into the

environment. Hence the objective of the study was selected as treatment of paddy soaked wastewater

through filtration against the gravity. The paddy soaked wastewater was collected from KRS mill at

Chunnakam. The filter tank, different media beds and storage unit were designed.pH TDS, EC,

turbidity, COD, BOD, phosphate and nitrate were analyzed in inlet and outlet of the filter tank.

Different combinations of the medias such as different sizes of gravels, charcoal, coarse sand, and fine

sand were used as filter media. The removal efficiency, reduction rate and changes were estimated.

The statical analysis was done by CRD.Combination of filter bed, gravels + charcoal + coarse sand +

fine sand had highest significant reduction in all measured parameters. Parameters were reduced to the

CEA recommended value for irrigation except BOD and COD. These parameters are also possible to

bring done in designed filter bed in the field.

Keywords: Effluent, filter bed, Media, Parboiling,Soaking


204

SECM/13/223

SEDIMENT AND SURFACE WATER QUALITY OF SELECTED TANKS IN

KILINOCHCHI

T.Abiramy1, M.Thusyanthi

2, H.B. Asanthi

3

1,2

Department of Agricultural Engineering, Faculty of Agriculture, University of Jaffna



3Department of Limnology, Faculty of Fisheries and marine science and Technology University of

Ruhuna

Abstract

Kilinochchi is the potential agricultural area for agriculture where surface water is a source for

irrigation. However quality of irrigation water has to be maintained to get quality crop yield. Physico

chemical quality of sediment play key role in water quality of tank water. There are no any attempt

has been taken to monitor the sediment quality so far. It is needed to investigate sediment analysis to

conserve agricultural aquaculture activities in future. Hence the objective was selected as to estimate

the quality of sediment in selected tanks namely Kilinochchikulam, Kanagambigaikulam,

Puthumurippukulam, Akkarayankulam and Kanthankulam via physic chemical analysis of bottom

tank sediment and surface water. The surface water pH, EC, sediment pH, sediment EC, organic

matter content, water holding capacity, phosphate, nitrate and sulphate content of sediment, were

measured during April and July 2013. Water and sediment sampling was done in five different

location in a perticular tank. Based on the result there were significant difference between the tanks

and soon after rainy season and during the driest period. But, there were no significant different

among the tested parameters within the tank except organic matter content. Considering the pH and

EC of surface water, all the tanks water was with recommended level for irrigation. Sulphate

concentration was very high but could not find the reason. Sediment pH was ranging from 5.42 to

7.31 in April and 4.44 to 6.6 in July. The low pH of the sediment would be influence the mobilization

of the heavy metals. Water holding capacity of sediment also had significant correlation with sulphate

concentration, nitrate concentration of sediment at 0.05 levels. Alkalinity of the sediment and

phosphate were significantly correlated. Comparing selected tanks, Puthumurippukulam had

significantly high in EC during dry period.

Keywords: Sediment quality, tank surface water, Kilinochchi tank


205

SECM/13/224

DURABILITY OF REINFORCED CONCRETE STRUCTURES SUBJECT TO CHLORIDE

INGRESS: COMPARISON OF MODEL PREDICTION WITH OUTCOME OF INSPECTION

DATA

Samindi Samarakoon1,Jan Sæleensminde

2,Cecilie Myklebust Helle

3

1Department of Mechanical and Structural Engineering and Material Science, University of Stavanger

(UiS), Stavanger, Norway


2Betec As, Bergen, Norway


3Department of Mechanical and Structural Engineering and Material Science, University of Stavanger

(UiS), Stavanger, Norway

Abstract

Durability of concrete structures is an important measure that must be evaluated. The durability of

concrete structures is affected by corrosion of steel reinforcement. Chloride-induced corrosion is one

of the major reasons for deteriorating of marine concrete structures. There are various models

developed to predictthe service life of a structure which includes the time to initiate and time to

propagate corrosion. Probabilistic models become more robust than deterministic approaches due the

inherent randomness observed in this process. Therefore, the durability of concrete structuresis more

realistically represented using probabilistic approaches. Similarly, it is vital to inspect the structure

after several years of exposure using destructive or non-destructive testing to update the service life

prediction models and toschedule the proactive maintenance for concrete structures. This paper

presents a case studywhich compares theoutcome from service life prediction model with inspection

data from a non-destructive method (i.e. potential mapping).

Keywords: Durability, chloride ingress, corrosion initiation, probabilistic models



206

SECM/13/225

LESSONS FROM ENGINEERING REPORTING SYSTEM AND DOCUMENT

MANAGEMENT SYSTEM IMPLEMENTED AT DICKOWITA FISHERIES HARBOUR

PROJECT, SRI LANKA

Haadi M.S.B.1, Fernando W.J.B.S.

2

1Civil & Structural Engineering Consultants (Pvt) Ltd

Tel:077 106 76 06


2Civil & Structural Engineering Consultants (Pvt) Ltd

Telephone:0714 216 681


Abstract

In Civil Engineering practice, various forms of documents are encountered regardless of whether in

design offices or in construction sites. While some of them are related to contractual correspondence

and reference purposes, others play an important role in communication of various issues at various

levels to a variety of users. In this context it is important to maintain a high level of standard in all of

these documents as they should reflect the level of professionalism expected of an Engineer and as

they can significantly contribute to the „Perception on Civil Engineers and the Civil Engineering

Profession‟ by the non-engineering professionals.

This paper is based on the systems and standards practised by BAM International (a Dutch firm who

was the Design and Build Contractor of Dickowita Fisheries Harbour Project) in relation to various

Engineering documents and document management practices. It is intended to disseminate good

practices in documentation into the Sri Lankan Engineering practice wherever appropriate.

Since this project itself is a Design and Build Contract and the project scope covers a variety of wide

ranging construction including marine related aspects as well as on-shore constructions, inevitably a

wide range of documents were produced and handled in relation to the project. This paper examines

several of such documents including Method Statements, ITPs (Inspection and Test Plan), JSAs (Job

Safety Analysis), Basis of Design Report, Option Study Report, Basic Design Report, Detailed Design

Report, etc with regard to its contents and importance, as well as other related issues. In addition this

paper emphasises on some effective document management techniques adopted during the project and

some effective value adding activities practised such as IDC (Inter-discipline Checks).

207

SECM/13/226

PERFORMANCE EVALUATION OF THE SEWAGE TREATMENT PLANT OF JAFFNA

TEACHING HOSPITAL

M. Senthilnanthanan1A. Santhan

2, S. Kumaran

3, S. Saravanan

4

1,2,3University of Jaffna, Jaffna


4National Water Supply and Drainage Board, Jaffna

Abstract

The Jaffna Teaching Hospital sewage treatment plant is situated within the city limits, away from the

hospital premises in a populated area. The treated effluent is discharged through an outfall into the

nearby shallow lagoon, where fishermen catch shellfish for the local market. Hence, efficient nutrient

and pathogen removal during the treatment of sewage is vital. Further, social impact of the plant is

also equally important.

This study, carried out from November 2012 to February 2013, focused on both aspects by conducting

laboratory based investigations for the former and focus group discussion and unstructured interviews

for the latter.

Water samples were collected every fortnight at six different points in the sewage treatment plant and

quality parameters were determined. The removal efficiency of BOD, COD, total suspended solids,

total-N content, phosphates and faecal coliforms were found to be 15.82, 38.15, - 0.82, 6.34, 13.25

and 4.60 % respectively. The same quality parameters of the treated effluent were found to be 83.12,

126.25, 30.87, 27.75 and 7.52 ppmand 54.5 MPN respectively.

The study on social impact of the plant revealed that its‟ existence causes unfounded fears and

anxieties in the minds of neighbours due to the release of objectionable odour from the plant.

Keywords: Sewage treatment, Jaffna Teaching Hospital, removal efficiency

208

SECM/13/227

STUDY ON THE GEOTECHNICAL PROPERTIES OF OPEN DUMPS IN SRI LANKA

U.P. Nawagamuwa1, W.D.S.P. Gunaratne

2, P. Kirubajiny

3, T. Thiviya

4, H.K.A. Priyadharshana

5

1Department of Civil Engineering, University ofMoratuwa, Sri Lanka.

Telephone:+94-71-832-8515; Fax:+94-11-265-1216



Telephone: +94-71-651-0735; Fax:+94-11-265-1216



Telephone: +94-77-196-8697



Telephone:+94-77-714-1335



Telephone:+94-71-543-0005


Abstract

Municipal Solid Waste (MSW) is an area which has got the attention of geotechnical engineers

currently with their researches, due to the requirement of land in order to cater increasing population.

Therefore, the focus has been on the MSW dumping yards to be used as construction sites.

Even though there have been researches all over the world regarding the characteristics of MSW with

respect to geotechnical engineering properties due to the variations of the compositions of MSW,

degradation conditions etc: all those results cannot be readily applied in Sri Lankan conditions under

the uncontrolled landfills. Therefore, this research study has been carried out to determine the

properties of three dump yards in Sri Lanka, with respect to their strength parameters, compaction

characteristics and compressibility characteristics.

Particle size distribution tests carried out on the collected samples showed that almost all the samples

are having a particle size distribution quite similar to coarse grained soils, with F0.075 in the range of

10% -20%. Standard Proctor compaction tests gave maximum dry densities in the range of 1000 –

1300 kg/m3 for these samples, which are quite low compared to traditional lateritic soils. Optimum

moisture contents corresponding to those Proctor compaction tests were lying in a range of 22% to

40%. Anyhow, working range of the moisture content for these samples was wider than traditional

soils, which ranged in between 15% to 50% for almost all the cases.

Direct shear (DS) tests were carried out on the samples with different moisture contents, as in the

Proctor compaction test showed that the variation in the friction angle ( ) was less compared to the

variation of the Cohesion Parameter (c kN/m2) with different moisture contents. Range for was in

between 18 – 21 as a whole, while the cohesion ranged between 10kN/m2 and 25kN/m

2.

Tests carried out in finding the compressibility characteristics of MSW mainly focused on primary

consolidation, which gave results in the range of traditional coarse grained soils. Anyhow, further

long term studies should be carried out prior coming up with conclusions with respect the

compressibility characteristics of MSW in Sri Lankan context.

Keywords: Municipal Solid Waste, Open dump yards, Mechanical properties of MSW



209

SECM/13/228

COST EFFECTIVE AND SPEEDY CONSTRUCTION FOR MEDIUM-RISE BUILDINGS BY

USING SYSTEM FORMWORKS

D.M.Wijesekara1 , W.D.A.D.Gunatillake

2

1Department of Civil Engineering

University of Moratuwa

Bandaranayake Mawatha, Katubadda, Moratuwa,Sri Lanka


2Sanken Construction (Pvt.) Ltd.

No. 295, Madampitiya Road, Colombo 14, Sri Lanka


Abstract

In a building construction project, to minimize the costs and to get the maximum profit the contractor needs

to complete the project as soon as possible and the client wants the building to use the building as early as

possible for the intended purpose. Formwork is one of the most important factors in determining the success

of a construction project in terms of speed, quality cost and safety. It accounts considerable amount of the

total project cost of the structure. In high-rise building construction the most efficient way to speed up the

work is by achieving a very short floor cycle. That directly depends on the selected form work type for the

construction. But it is same for the medium-rise buildings as well. This paper will present about the existing

formwork types in Sri Lanka and the available new techniques in formwork erection. This paper will clearly

present an analysis and comparison of costs and durations of selected projects when using different types of

formworks. The main objective of this paper is to identify the least no. of typical storeys required in a

building construction project, to use aluminium panel system formwork.

Keywords: system formwork, project duration, project cost, preliminary cost, typical storeys



210

SECM/13/229

INTEGRATED URBAN WATER SUPPLY USING OPTIMUM DIVERSION OF KALU

RIVER TOWARDS SOUTHERN SRI LANKA

Lakmal A.G.P.N.1, Kumarasiri H.K.S.

2, Sampath W.M.D.C.

3, Nandalal K.D.W.

4


Telephone: +94715375041; Fax: +94254580508



Telephone: +94783863783; Fax: Not available



Telephone: +94715374815; Fax: Not available



Telephone: +94775564217; Fax: +94812393500


Abstract

To meet the rising water demand in urban southern Sri Lanka, Kalu River is proposed to be diverted

to the southern area. This paper presents an application of a HEC-ResSim software based model to

investigate the possibility to divert Kalu River to the southern Sri Lanka by constructing a reservoir

system upstream of Rathnapura. Locations suitable for the reservoirs on the three tributaries of Kalu

River, viz., Rat Ganga, Bambarabotuwa Oya and Wey Ganga, were identified using the topo-maps of

the area. The reservoirs in the proposed system, which are connected in series, were modeled using

the HEC-ResSim software. Storage volumes of the three reservoirs were initially identified based on

mass diagram. The total possible diversion from the reservoir system towards southern Sri Lanka was

determined by the HEC-ResSim simulation model. Subsequently, sensitivity of the reservoir storages

was studied to identify the most suitable reservoir storage volumes to maximize the total water

diversion. The finally selected reservoir system is able to divert 262.3 MCM in a year at a system

reliability of 86.6%, towards southern Sri Lanka for urban water supply.

Keywords: Simulation, Reservoirs, Diversions, HEC-ResSim

211

SECM/13/230

SUSTAINABLE CONSTRUCTION IN PALESTINE

Adnan Enshassi1,Bernd Kochendoerfer

2

1islamic University Of Gaza


2berlin School Of Technology, Germany


Abstract

The environment-related problems in developing countries are acute. Sustainable construction has not

received sufficient attention in Palestine, though it is an important aspect of sustainable development

in developed countries as well as in developing countries. It is argued that sustainable construction

has to take place by understanding the political, economic, social and development issues of a

country, and that sustainable construction should become an integral part of sustainable development.

Palestine has fragile environment being faced with high levels of land degradation, acute shortage of

fresh water, and rapid urbanization with its associated problems of air pollution and pressure on

existing infrastructure such as waste management systems. The aim of this paper is to highlight the

sustainable development process in the construction sector, to present the environmental policies and

strategies in Palestine, to highlight the sustainable development process in the construction sector,

and to feature the potential barriers to their application. Palestine is facing some difficulties in the

effort to make sustainability an operative criterion in its new development activities, which include

lack of knowledge about the concepts of sustainability, lack of legal aspects and regulations, low

technology, and financial constraints. An active cooperation with international community and among

all construction participants is needed in order to realize the vision of sustainability.

Keywords: Construction, Development, Sustainability, Environment, Palestine

212

SECM/13/231

STRUCTURAL INTEGRITY CONTROL OF AGEING OFFSHORE STRUCTURES:

PRIORITIZING SMR SCHEME/TECHNIQUE FOR DAMAGED STRUCTURES

R.M. ChandimaRatnayake1, S.M.S. M.K. Samarakoon

2

Department of Mechanical and Structural Engineering and Materials Science,

University of Stavanger, N-4036, Stavanger, Norway.


Abstract

Structural integrity control (SIC) is vital for existing ageing as well as newly built offshore and

onshore structures. The SIC become highly sensitive to the interventionsunder a potential loss of

structural integrity (SI) when it comes to offshore oil and gas (O&G) production & process facilities

(P&PFs). This is mainly due to theinherent constraints present incarrying out engineering work in

theoffshore atmosphere. This is further exacerbated by the ageing offshore structures and necessity

ofcarrying out life extension at the verge of their design service lives. The local and international

regulations pose implementing appropriate strengthening, modification and/or repair (SMR) plans

when significant changes in the SI are revealed. In this context, SMR techniques such as welding,

member removal/reduction of loading, mechanical clamping and grouted repairs play a vital role.

Hence, making optimal decisions selectingan optimal SMR approach based on the particular

conditions isan important issue in assuring SI. This manuscript presents an approach selecting optimal

SMR approach using an illustrative case. Also, it provides comprehensive overview about currently

existing SMR techniques and their comparative pros and cons.

Keywords: structural integrity control, ageing offshore structures, SMR, multi-criteria decision

making



213

SECM/13/232

IMPACT OF MONITORING AND CONTROLLING ON TIME AND COST

PERFORMANCE OF CONSTRUCTION PROJECT

Adnan Enshassi1,Salam El Zebdeh

2

1,2

Islamic University of Gaza


Abstract

Monitoring and controlling are generally regarded as follow-up activities which ensure that planning

objectives and project objectives are fully achieved. The aim of this study is to investigate the impact

of monitoring and controlling on project performance at United Nations Relief and Works Agency for

Palestine Refugees in the Near East (UNRWA) construction projects.Data were collected from

archival records of 10 randomly selected construction projects and from structured questionnaires

distributed to 24 supervision engineers representing owners and contractors. Monitoring and

controlling factors were shortlisted form previous related research studies and the input of local

professionals. The results revealed that UNRWA supervising engineers carry out projects monitoring

and controlling functions more or less at the same level of frequency of contractors' supervising

engineers. The results indicated that the frequencies of project monitoring and controlling parameters

practiced by the contractors have no significant correlation with the project performance concerning

cost-overrun or time-overrun. UNRWA`s engineers practicesof project monitoring and controlling

were found not very effective in reducing cost-overrun and time-overrun of the projects they have

supervised.Capacity building for all UNRWA supervision staff is required in order to ensure a full

understanding of monitoring and controlling functions. It is hoped that this studywill assist both

UNRWA engineers and contractors' management team to utilize their efforts on project monitoring

and controlling more effectively in order to improve the project performance.

Keywords: Construction projects, Monitoring, Controlling, Performance, Gaza Strip

214

SECM/13/233

DOWN-FLOW ANAEROBIC FILTERS PACKED WITH ORGANIC AND INORGANIC

WASTE MATTER TO TREAT LANDFILL-LEACHATE

V.P.H.S.Vidanapathirana1, M.P.Siriwardana

2, B.S.R Nanayakkara

3,W.K.C.N Dayanthi

4

1Telephone: 0718034518


4Telephone: 0714475693


Abstract

The landfill leachate consists of different organic and inorganic compounds having a high potential to

contaminate ground and surface water threatening the human health, if not removed before disposal.

Anaerobic filters have emerged as a promising technology for landfill-leachate treatment. The major

drawback with the system is that the packing media are expensive. There is very few past research

available in the literature on laboratory experiments of anaerobic filters with waste matter as packing

media. Hence the aim of this study was to assess the removal efficiencies of the contaminants found

in landfill-leachate by laboratory-scale down-flow anaerobic filter columns packed with several types

of organic and inorganic waste matter. The experimental set-up consisted of four columns each with

150cm media height and 8.9cm inner diameter. The four columns were filled with dewatered sludge;

fire-wood charcoal; silica sand and a mixture of coconut coir fiber, saw chips, rice husks and rice

straw, respectively. All columns were continuously loaded with 10 % landfill leachate collected from

a dumpsite. Every day, the effluent was characterized. There was a reduction in COD, BOD5 and

nitrogenous compounds such as ammonia and total-N.

Keywords: Down-flow anaerobic filters, waste matter, packing media, organic matter, nitrogenous

compounds



215

SECM/13/235

AN EFFECTIVE NEURAL NETWORK ENSEMBLE ARCHITECTURE FOR SHORT

TERM RAINFALL FORECASTING

H.R.K. Nagahamulla 1, U.R. Ratnayake

2, D.A.A.C. Ratnaweera

3

1Department of Computing & Information Systems,Wayamba University of Sri Lanka, Sri Lanka.

Telephone: Number +94 777 808651


2Institute Teknologi Brinei, Brunei



Telephone: +94 81 2393627


Abstract

Many water related planning and management activities are dependent on quantitative rainfall forecasts.

Increasing the accuracy of the rainfall forecast is a widely researched area in time series forecasting. Out of

many available forecasting techniques Artificial Neural Networks (ANN) methodology is one that yields

more accurate forecasts. The main objective of this study is to investigate the use of different Neural

Network Ensemble techniques in the context of Rainfall Forecasting.

Several Ensemble Neural Networks (ENN) are created with different combinations of General Regression

Neural Networks (GRNN). The member GRNN are trained for ENN1 by varying the initial random

weights and for ENN2 by varying the training data. The different training data sets are obtained by moving

block bootstrap technique. Both ensembles are combined using average, weighted average and stacked

methods separately. The selected study area is Colombo, Sri Lanka. Daily observed weather data from 1961

to 2001 are used to train, validate and test the ensembles.

The performance of ensembles are compared with each other and the performance of a single GRNN. The

results show that the ensemble models yield better results than the single GRNN and the best prediction

accuracy is obtained by ENN2 combined with stacked method.

Keywords: Artificial Neural Networks (ANN), Bootstrap Techniques, Ensemble Neural Network (ENN),

General Regression Neural Networks (GRNN)




216

SECM/13/236

SELECTION OF SUITABLE SITES FOR LAND FILLING OF SOLID WASTES USING GIS

INTEGRATED WITH ANALYTIC HIERARCHY PROCESS (AHP): A CASE STUDY FOR

THE GALLE MUNICIPAL COUNCIL AREA

A.G.O.A. Chathuranga1, J.K.A.L. Darshaka

2, A.G.A. Wanshanatha

3,W.K.C.N Dayanthi

4

1Department of Civil &Environmental Engineering, University of Ruhuna, Sri Lanka.



2Department of Civil & Environmental Engineering,University of Ruhuna, Sri Lanka.



3Department of Civil &Environmental Engineering, University of Ruhuna, Sri Lanka.



4Department of Civil&Environmental Engineering, University of Ruhuna, Sri Lanka.

Telephone: +94714475693


Abstract

Landfilling is one of the primary methods of municipal solid waste disposal.Appropriate selection of

landfill site is an important issue due to enormous impacts on the economy, ecology, environment and

public health. The aim of this study was to use GIS technology and multi-criteria decision technique

called „Analytic Hierarchy Process (AHP)‟ in finding suitable landfill sites for solid waste disposal in

the study area and to evaluate the existing landfill sites. Several factors were considered in the siting

process including surface water bodies, forest reserves, wetlands, town and village centers, coastal

belt, important buildings, transportation network and land use pattern. Weights were assigned to each

criterion depending upon their relative importance and relative magnitude of impact using AHP. The

weights were incorporated into GIS environment to determine suitability of landfill sites in study

area.The study revealed that the present dumpsite of Galle Municipal Council was categorized as

moderately suitable for landfill siting.

Keywords: Land filling, GIS, AHP,Siting


217

SECM/13/237

SEISMIC AND GRAVITY LOADING ANALYSIS FOR THEFORTH RAIL BRIDGE

SCOTLAND USING SAP2000 V.14

Hussain Jiffry

BEng Civil & Structural Engineering, School of Engineering Design &Technology, University of

Bradford UK


Abstract

The phenomenon of earthquakes and seismic effects has been far too old and the study on seismic

response on manmade structures has been far too young to understand its true response on structural

behaviour. The in depth-science of earthquakes has been a mystery still to this date where no can

precisely predict when it is going to occur how it is going to occur and what consequences in would

bring into to the structures. Therefore it is very important in this day and age to at least predict the

response on structural and non-structural elements with the past events. Many scientist and

seismologist and engineers have been working intensely on this subject because the general

consequence it brings is often catastrophic, devastating and fatal.

This paper performed seismic analysis of the Forth Rail Bridge Scotland through response spectrum

analysis method using SAP2000 V14, and analysed the critical loading pattern due to the gravity

loading. Forth Rail Bridge is one of the most iconic engineering marvels ever builtone of the heaviest

and stiffest structures ever made in steel. Its unique structural behaviour and system still amazes

current engineers. The other most important study in this paper is the parametric study on how this

bridge behaves due to different intensities of earthquakes and application of different code practices

using the response spectrum function to analyse its out puts..

Keywords: Earthquakes, Response spectrum,cantilever, Eurocode

218

SECM/13/238

WATER QUALITY ASSESSMENT OF DRINKING WATER: A CASE STUDY AT

RAJARATA UNIVERSITY OF SRI LANKA, MIHINTHALE

E.M.Herath 1, Meththika Vithanage

2

1Department of Biological Sciences, Faculty of Applied Sciences, University of Rajarata, Sri Lanka

2Chemical and Environmental Systems Modeling Research Group, Institute of Fundamental Studies,

Kandy, Sri Lanka

Tel: +94 812 232 002


Abstract

This study was designed to assess the water quality of piped water and bottled water usage among

Rajarata University community through chemical analysis. As chemical parameters pH, Electrical

conductivity, Chloride, free residual Chlorine, Alkalinity, Ammonia, Nitrate, Nitrite, Fluoride, Total

phosphate, Total hardness, Dissolved Oxygen (DO), Aluminum, Total iron and Sulfate were analyzed.

As microbiological parameters, total and fecal coliforms were measured using membrane filtration

technique for five months in five different places through the tap water line from Nuwara Wewa to the

University premises.

Results showed that most parameters are within the SLS permitted levels. However total coliforms

count and the Aluminum concentrations were shown exceptional from the SLS permitted levels.

According to the SLS 614:1983 maximum permissible level of coliform bacteria is 10 per 100 ml.

However, 36 coliform bacteria were resulted per 100 ml. The Aluminum level is 0.2 mg/l but in our

data it reached to 2.3 mg/l may be due to the addition of alum during treatment. The amount of

Residual Chlorine is very low, most of the time not detectable, in the University premises. Maximum

permissible level is 0.2 mg/l. It may be the reason for the high total coliforms count. According to

questionnaire data 64 % use bottled water as their drinking water source of that, 72.9 % were using 20

L bottles.

Keywords: Water quality, Coliforms, Pipe borne water, Residual chlorine

219

SECM/13/239

DEVELOPMENT OF EFFICIENT PACKED-BED UP-FLOW ANAEROBIC FILTERS

USING LOW-COST AND LOCALLY AVAILABLE MEDIA TO TREAT LANDFILL-

LEACHATE

Nanayakkara B S R,Vidanapathirana V P H S, Siriwardana M P, Dayanthi W.K.C.N, Priyankara N H,

Alagiyawanna A M N


Abstract

Poorly managed and unregulated landfills are the most common sites in many developing countries.

The open dumping of solid waste has initiated a lot of environmental, social and economical

problems. When accounting the existing remedial measures of the well-designed landfills and their

features and implications, the possibility of adopting them could be considered with some enhanced

technical and economical solutions that suit the country.

Leachate treatment is one of the main features in well-designed landfills. As the most of municipal

waste consists of biodegradable waste, anaerobic filters well suit to the leachate treatment. As the

packing media used for this treatment is highly expensive, finding suitable readily available and low-

cost packing media for anaerobic filters is a timely need.

Therefore, the performances of locally available and low-cost organic and inorganic packing media in

treating landfill leachate were studied using a laboratory scale experimental set-up consisting of four

packed-bed up-flow anaerobic filter columns. The height and diameter of the cylindrical shaped

packed bed were 50 cm and 9 cm, respectively. The columns were filled with silica sand, dewatered

sludge, fire wood-charcoal and a mixture of rice husks, rice straw, and coconut coir fiber and saw

chips, respectively. Initially, the columns were flushed with tap water until there was negligible

amount of contaminant found in the effluent. Thereafter, each column was loaded with 10 % landfill

leachate. Every day, the effluent was characterized. There was a reduction in COD, BOD5 and

nitrogenous compounds such as ammonia and total-N.

Keywords: Up flow anaerobic filters, Organic matters, Nitrogenous compounds,Packing media

220

SECM/13/240

FREE VIBRATION BEHAVIOUR OF FIBRECOMPOSITE SANDWICH BEAMS WITH

DEBONDS

W. Karunasena1, I. Jayathilake

2, W. Lokuge

3

1Centre of Excellence in Engineered Fibre Composites

School of Civil Engineering & Surveying

Faculty of Health, Engineering and Sciences, University of Southern Queensland, Queensland,

Australia.

Telephone: Number +61 7 4631 2906 Fax: +61 7 4631 2526





Australia.

Telephone: Number +61 7 3470 2906





Australia

Telephone: Number +61 7 3470 4477


Abstract

Although perfect bond between the skin and the core is a common assumption, an important issue

that needs to be considered in using a composite beam or slab is the development of debonding

between the skin and the core. Debonding refers to separation of skin from the core material in

composite sandwiches. Although much research has been carried out to investigate dynamic

behaviour of fully bonded composites, research on this aspect for debonded composites is scarce.

This study concentrates on investigating the dynamic behaviour of fibre composite sandwich beams

with debonds. A parametric investigation is carried out to assess the influence of various parameters

of concern including length and width of the debond, location of debond, size and support conditions

of the beam on the free vibration behaviour, using the finite element package Strand7. In the model

developed with Strand7, rigid links and master slave links are used to connect skin and core in

bonded and debonded regions respectively. Published results for free vibration behaviour for GFRP

panels will first be used to compare the analytical results to validate the developed

model.Furthermore a spring model is implemented between the skin and the core of debonded beams

to take the probable contact conditions into account.

A general reflection through the parametric investigation is that the extent of natural frequency

variation with respect to debonding length increases with the order of the natural frequency. Further it

is observed that the change in frequency with change in debonding length is much more significant

for the full width debonding when compared to half width debonding. It is also perceived that the

extent of variation of natural frequency due to debonding in composite beams depends on the degree

of contact anticipated in the debonding region.

Keywords: Sandwich composite beams, Glass fibre-reinforced polymer, Dynamic behavior,

Debonds, Finite element modeling







221

SECM/13/241

PROVISION OF SANITATION SYSTEM TO ALL THE HOUSES WITHIN 10KM RADIUS OF

GITAM UNIVERSITY USING DRDO- BIODIGESTER SANITARY TECHNOLOGY

Sahil Mathur1,Dibyatanay Joardar

2, Varun Singh

3, A.Sriharsha

4, Ankit Gupta

5 , M.Srikesh

6

1, 2, 3, 4, 5, 6. Engineers Without Borders – India, GITAM University, Hyderabad


Abstract

“Knit one and kill two”. Sounds instantly appealing; and so is this project of DRDO-Biodigester

Sanitary system where both the problems of water and sanitization are soughed out. In India, where

about more than half of the total population are laboured to go for open defecation system and 30% of

it do not get access to water in summers , may be due to their poor financial condition or lack of

awareness, require an adaptation of a proper sanitary and water system. This paper discusses an

intervention strategy related to environmental sanitation and water, which inturn aims in bringing

sanitation facility to all the houses without sanitation system around 10Km radius of GITAM

University and increasing the ground water table simultaneously.

DRDO Bio Digester Bacterial sanitation consists of bacteria, which converts the human excreta into

water. The water can percolate into the ground and increase the ground water table without

contaminating it. It has COD, BOD, pH, E.Coli of 56ppm, 7ppm, 6.8-7 and less than 1 %

respectively. These bacteria sustain in any temperature, it can also resist acid. The core technology

here, equals of anaerobic bacteria adopted to work at a temperature lower than 5‟C.This is the

component which converts organic waste into methane, carbon dioxide and water. The above gases

released can inturn be used for other useful purposes. The complete system comprises of a toilet cabin

with a pan and the Biodigester tank.

For maintenance a committee is formed, which comprises of the owner of the sanitation system,

EWB-GITAM Student Chapter and Village Panchayat,. This idea of maintenance provides

employment as a maintenance worker of the sanitation system. The implementation of this project

will reduce the health hazards sourced from the harmful insects/organisms. It will also improve the

life condition of people and will abolish the sexual harassment faced by women.

Keywords: DRDO-Biodigester, Bacterial, Sanitization


222

SECM/13/242

LESSONS FROM 2010/2011 NEW ZEALAND EARTHQUAKES

Najif Ismail1

1School of Architecture Building and Engineering, Otago Polytechnic, New Zealand.

Telephone: +64 3 474 2851; Fax: +64 3 4796191


Abstract

Of several hundred M5 and above seismic events recorded in New Zealand, the M7.1 earthquake of 11

September 2010 and the M6.3 aftershock of 22 February 2011 are known to be the most devastating in the

history of New Zealand.These earthquakesleft several hundred buildings partially or completely collapsed in

Canterbury region, whereas substantial ground movement resulting due to liquefaction also necessitated

deconstruction of a few more.Theground motion records of these damaging earthquakes are presented and

unique characteristics of these seismic events are discussed briefly. A summary of post-earthquake

structuralassessment and performance inspections conducted on as-built and strengthened historic buildings

is then presented along with some key statistics acquired by interrogating the assessment data. Later the

implications of these earthquakes for other major cities of the country are discussed and an overview of a

recent project undertaken in Dunedin to investigate the seismic vulnerability of historic buildings is

presented. The experiences of the earthquakes have prompted review of existing standards, policies and

practices, which are discussed finally in the presentation.

Keywords: Earthquake, performance, seismic, vulnerability, mitigation


223

SECM/13/243

ATMOSPHERIC PARTICLES AS A POLLUTANT SOURCE IN THE URBAN WATER

ENVIRONMENT IN SRI LANKA – CURRENT RESEARCH TRENDS AND FUTURE

DIRECTIONS

A.M.M. Ziyath1,3

, M. Vithanage2, A. Goonetilleke

3

1Department of Chemical and Process Engineering, University of Peradeniya, Sri Lanka

Telephone: +94812393694


2Chemical and Environmental Systems Modeling Research Group, Institute of Fundamental Studies,

Kandy, Sri Lanka

Telephone: +94812232002; Fax: +94812232131


3Science and Engineering Faculty, Queensland University of Technology, Australia

Telephone: +61731381539; Fax: +61731381170


Abstract

Human and ecosystem health impacts imposed by water pollution are a major problem in the urban areas of

Sri Lanka. A primary source of pollutants to urban water sources is atmospheric particles. Hence, it is

important to develop a detailed understanding of atmospheric particle characteristics, their sources of origin

and the transport pathways. Several research studies have been conducted in Sri Lanka on atmospheric

pollution and these studies have tended to differ in their scope, study region and the investigated pollutants.

The objectives of this paper are: (1) to report the outcomes of a detailed state-of-art literature review of

atmospheric pollution related studies in Sri Lanka to understand the current trends and (2) to discuss the

future research activities necessary to generate the important knowledge required for the development of

effective strategies to control the adverse impacts of atmospheric pollution on urban waterways.

Keywords: Atmospheric pollution, Atmospheric deposition, Stormwater pollution, Road build-up

224

SECM/13/244

ANALYTICAL CYCLIC CONSTITUTIVE MODEL FOR CONFINED CONCRETE

IMPLEMENTATION IN OPENSEES: CONFINEDCONCRETE02

T.L. Pradeep1, F. Braga

2, R. Gigliotti

3, M. Laterza

4, M. D‟Amato

5

1Department of European Cultures and Mediterranean, University of Basilicata, Italy.

Telephone: +39 32 77 810108


2Department of Structural and Geotechnical Engineering, “Sapienza” University of Rome, Italy.

Telephone: +39 06 4458 5751


3Department of Structural and Geotechnical Engineering, “Sapienza” University of Rome, Italy.

Telephone: +39 0644585 5157



Telephone: +39 32 93606188



Telephone: +39 3478070752


Abstract

This paper presents the new material developed inside the OpenSees by considering constitute model

for the concrete subjected to revere cycling and monotonic loading. The new material intended to

provide the ability of model the cyclic behaviour of concrete subjected to compression in the

computational programme. The analytical formulation proposed by the Braga, Gigliotti and Laterza

(BGL model, 2006) is used for the envelope and reverse (loading and reloading) action of the material

govern by the Yassin (1994) approach, which is given bilinear curve for unloading and loading.

The lateral confinement of concrete enhances the strength and durability of the reinforcement concrete

significantly. Introducing this uniaxial material inside the OpenSees is capable to model the influence

of transverse hoops, ties and/or FRP, external wrapping with the section considered. Many numbers of

great researches have been conducted to understand the real compressive and tension behaviour of the

reinforced concrete based on the experimental programme and analytical formulations. Research on

cycling response of concrete is becoming a challenge of the earthquake engineering for modelling and

capable prediction of hysteretic characters of the reinforced concrete. This research work is devoted to

develop the computational methods to model and analyse the reinforced concrete structures subjected

to revere cycling specially by applying the confinement influence to section (Beam, column or joint

panel).

Keywords: Reinforced Concrete, Confinement, Cyclic Load, Axial Stress, Axial Strain, Stiffness




225

SECM/13/245

EFFECT OF EXTERNAL CFRP CONFINEMENT ON SHEAR BEHAVIOR OF RC BEAMS

Franklin F.R Frederick1, U.K. Sharma

2, V.K. Gupta

3

1Department of Civil Engineering, IIT Roorkee, India

Telephone: +91-9458947807



Telephone: +91 1332 285877



Telephone: +91 - 1332 - 285441


Abstract

Debonding of fiber reinforced polymer (FRP), particularly in shear, is a major failure mode when

using FRP sheets to strengthen concrete structures. This paper presents an experimental study on the

performance of reinforced concrete (RC) T-beams strengthened in shear using external CFRP

wrapping with anchorage method. The main objective of this study is to evaluate the effectiveness of

anchorage system for RC beams strengthened using externally bonded (EB) FRP methods. The results

of this study reveals that specimens retrofitted using EB FRP with specially designed anchorage

system can achieve a superior contribution in shear resistance compared with specimens strengthened

using EB FRP without anchorage method. The beam strengthened with CFRP wrapping shows better

performance in load carrying capacity and ductility as compared with the control beam.

Keywords: RC Beam Strengthening, CFRP, Shear behavior, External anchorage.



226

SECM/13/246

A WEB-BASED SOFTWARE APPLICATION FOR ASSET MANAGEMENT OF

COMMUNITY BUILDINGS: CHALLENGES IN DEVELOPMENT, DATA INPUT AND

FORECASTING

K.M. Atapattu1,S. Setunge

2, G. Zhang

3,H. Mohseni

4

1School of Civil, Environmental & Chemical Engineering, RMIT University, Melbourne, Australia

Telephone: +61412389154








Abstract

Community buildings are one of the largest infrastructure assets invested and managed by local

governments in Australia. An optimised expenditure projection model which ensures building assets are

sustained at a required level of service requires a reliable deterioration model for building components.

Prediction of deterioration as well as decision making methods for community buildings have been explored

by RMIT University in a research project conducted in collaboration with six Australian local councils and

the Municipal Association of Victoria.

A web-based software tool has been developed at RMIT University to enable buildings asset managers to

make informed decisions for maintenance and rehabilitation activities of building assets. The software tool

uses a probabilistic deterioration prediction model to reflect the stochastic nature of condition degradation to

model variety of building components. Risk and expenditure forecasting based on Markov Chain

deterioration prediction are generated within the program. Consequently, scenario analysis assists not only

in organisational risk threshold identification based on levels of service, but also in funding allocation to

attain required building performance. The software integrates a quadruple bottom line sustainability factors

to enable decision makers in considering environment, social, economic and functional aspects of decisions

for community buildings.

The paper presents the algorithm of the software, challenges in integrating multiple modules, the analytical

modules, input data and outcomes of forecasting for a data set from a City Council in Victoria, Australia.

Keywords: Condition monitoring, buildings, condition aggregation





227

SECM/13/247

ELECTROCHEMICAL OXIDATION TECHNIQUES FOR URBAN WATER

MANAGEMENT

P.B. Jayathilaka1, G.C. Pathiraja

1, D. Subasingha

1, A. Bandara

2,N.Nanayakkara*

3


Telephone:+94 772352071; Fax: +94 812232001



Telephone: +94 779021621); Fax: +94 812232001



Telephone: +94 812 232 002); Fax: +94 812232001


2Department of Chemistry, University of Peradeniya, Sri Lanka.

Telephone: +94 81 239 (4449); Fax: Number



Telephone: +94 812 393567; Fax: +94-81-2388158


Abstract

Urban water bodies have been more polluted by organic pollutants than the non-urban water bodies mainly

due to addition of industrial effluents. Since these urban water bodies are the major sources of drinking

water supply, their quality management is important. In order to enhance the usefulness of urban water

environment, developing techniques to treat water polluted with organic chemicals are essential. Among

these different water treatment techniques, knowledge on electrochemical oxidation is more attractive. Since

anode material plays big role in effective electrochemical oxidation process, development of anode

materials with higher oxidation efficiency is needed.

However, limited studies have been reported in literature towards the development of anode materials

for specific contaminants in water. Therefore, the aim of this study is to develop anode material to

electrochemical mineralization of phenol, a major urban water polluter, as a model compound. In

order to accomplish the above objective, different anodes were developed. Experiments were carried

out at a constant current density of 20 mA/cm2

in Na2SO4 medium at room temperature for 6hrs to

study anodes efficiencies. Cyclic voltammetry anodic charge analysis of different anodes proved

Ti/IrO2-Sb2O3 as the best anode in removing phenol. The experimental findings suggest that the

electrochemical oxidation can be one of the best options in treating organic pollutants in urban water

sources.

Keywords: Electrochemical oxidation, Dimensionally stable anodes, Organic pollutants, Urban water

management





228

SECM/13/248

INVESTIGATION OF FLEXURAL BEHAVIOUR OF RCC BEAM USING GFRP BAR

1T.Saraswathy,

2K.Dhanalakshmi

1Department of Civil Engineering, Anna University, Tamilnadu.



2University College of Engineering, Nagercoil

Abstract

Glass Fibre Reinforced Polymer bars posses mechanical properties different from steel bars, including

high tensile strength combined with low elastic modulus and elastic brittle stress- strain relationship..

Due to the linear elastic brittle behaviour of GFRP bars, the flexural behaviour of GFRP reinforced

concrete beam exhibit no ductility. GFRP reinforced concrete beams must be over reinforced so that

they fail by concrete crushing rather than by rebar rupture. The flexural capacity of the beam was

computed by sectional analysis in which the rebar is assumed to maintain perfect bond with the

surrounding concrete. In all these work the lon gitudinal reinforcement is assumed to be perfectly

bonded to the surrounding concrete at failure. The low modulus of elasticity of GFRP rebar resulting

in relatively large deformations and smooth surface characteristics of the GFRP leading to debonding

type of failures are important in determining the serviceability performance of GFRP reinforced beam

sections. Hence the serviceability constraints generally will control the design of the GFRP reinforced

beam sections. The unique advantages of GFRP materials such as excellent resistance to corrosion,

high strength to weight ratio, electromagnetic neutrality and ease of handling make these materials

potentially suitable for the use in reinforced concrete under conditions where conventional steel

reinforced concrete has resulted in unacceptable serviceable problem.

The current research program was carried out to investigate failure mode, load deflection behavior

and crack pattern. In this study, flexural behaviour of rectangular concrete beams reinforced with

glass fiber reinforced polymer will be examined with manufacturing 4 specimens. Considering the

constant length and diameter of bars are used with various bar in tension and compression zone. In

one beam made with control specimen of 12mm diameter Fe415 bar in tension zone and 10mm

diameter bar in compression zone. Second beam made with 12mm diameter GFRP bar in tension zone

and 10mm diameter Fe415 in compression zone. Third beam made with 12mm diameter Fe415 in

tension zone and 10mm diameter GFRP bar in compression zone. Fourth beam made with 12mm

diameter GFRP bar in tension zone and 10mm diameter GFRP bar in compression zone. In most

cases of RC beams without GFRP bars, flexure failure, shear failure and the combination of failure

modes were observed. On the other hand, beams strengthened with FRP bars failed in shear. Failure

of the GFRP reinforced concrete beams was mainly due to its reduced post cracking stiffness and the

slip between rebar and the concrete matrix.GFRP bars have a weaker elasticity modulus, which

generate more deflection for equal loads and span. After the first crack, beams reinforced with low

stiffness GFRP bars in general deflected more rapidly and non-linearly with moment up to the

ultimate moment. The load deflection response of the various GFRP reinforced beams have been

predicted and seems to closely predict the corresponding experimentally observed response.

Keywords: GFRP Bar, ultimate moment, Deflection, Crack Pattern, Flexural Behaviour



229

SECM/13/249

LANDFILL-LEACHATE TREATMENT BYPERMEABLE REACTIVE BARRIERS (PRBS)

WITH WASTE MATTER AS REACTIVE MEDIA

Chathura Arthanayaka, Asiri Kariyawasam

University of Ruhuna, Sri Lanka


University of Ruhuna, Sri Lanka


Abstract

The leachate dissipating from landfills is rich in contaminants and possesses high potentials to

contaminate surrounding ground and surface water. Therefore, leachate should undergo treatment

before entering ground and surface water. Most of the existing leachate treatment methods belong to

the „pump- and- treat‟ category, which are unaffordable because of high cost. Hence, a low cost

treatment method plays a vital role. PRBs which are widely applied to remedy the contaminated

ground water can be applied as an in-situ method for leachate treatment. Once installed PRBs require

less attention and cost for operation and maintenance. Therefore, it is imperative to investigate how to

reduce cost of PRBs maintaining high efficiencies concurrently. The availability and cost are

important criteria in selecting reactive materials for permeable reactive barriers (PRB). In this study, a

laboratory scale column experiment was conducted to studythe removal efficiencies of contaminants

contained in landfill leachate by PRB using several types of waste matter as reactive media. The

column experimental set-up consisted of 4 columns. Each column was filled with dewatered sludge,

demolished waste, quarry dust and mixture of coconut coir fiber, rice straw, saw chips, and rice husks,

respectively. Each reactive material was mixed with laterite soil so that soil to reactive material ratio

became 4:1 on weight. Initially, the columns were flushed using tap water in order toremove readily

flushable contaminants. Then, the columns were loaded with 5% leachate collected from a dumpsite.

The hydraulic and physical parameters of reactive material in each column were measured before and

after loading columns with leachate. During the experimental series, influent and effluent samples

were collected and analyzed for several wastewater parameters including organic and nitrogenous

compounds. There was aconsiderable reduction in each waste water parameter in the effluent samples.

Keywords: column tests, leachate, Nitrogenous compounds, organic materials, Reactive media


230

SECM/13/250

EFFECT OF WATER/CEMENT (W/C) RATIO ON STRENGTH DEVELOPMENT OF

CONCRETE (EXPERIENCE IN SMALL TO MEDIUM CONSTRUCTION WORKS)

Thushara Priyadarshana1, Gamini Chandrasena2, Ranjith Dissanayake3



2 I&AInnovation & Application Center, Holcim (Lanka) Limited, Colombo 14, Sri

Lanka


3Dept. of Civil Engineering, University of Peradeniya,

Peradeniya 20400, Sri Lanka


Abstract

This research focuses on the variation of water to cement (w/c) ratio and its effect on strength of concrete. It

was found that average w/c ratio used in most small to medium construction works are around 0.70 to 0.80

(35 l to 40 l per 50 kg cement bag), all 5 cement brands shows almost similar behaviour in different w/c

ratios and strength drop is around 50% when it reaches higher water cement ratios (0.70 and 0.80) compared

with desired w/c ratio of 0.55 for these type of construction works. The lost due to these bad practices in Sri

Lanka cost the nation, and heavily affect the sustainability of built structures.

Keywords: water in concrete, water/cement ratio, strength of concrete, w/c ratio,



231

SECM/13/251

A REVIEW OF PRESSURE TRANSIENT EFFECT ON WATER DISTRIBUTION MAIN

FAILURE

R.M.S.U.P. Rathnayaka, J. Kodikara, P. Rajeev, D. Robert

Dept. of Civil Engineering,Monash University, Clayton,VIC, 3168, Australia.



Abstract

This paper presents review of studies on pressure transient effect on water pipeline failure. Water

distribution mains in the world are becoming older and more and more prone to failure. Prediction of

pipe failure becomes very important as failure of large diameter pipes can cause property damage,

heavy traffic as well interruption to the water supply.The most challenging task is accurate prediction

of these failures as it depends on several factors, which are very hard to estimate accurately. Failure

predictions of water distribution pipe lines are depending on several factors such as internal water

pressure, traffic load, pipe corrosion etc. Most failure occurs as a result of combinations of two or

more factors mentioned above. Evaluation of steady state as well as transient pressure in the water

main is particularly important to predict pipe failure. Comprehensive pressure transient modelling and

calibrating of models are required to obtain proper loading to predict pipe failure. This paper reviews

importance of understanding pressure transient effect to predict distribution mains failure, available

analysis techniques, and important considerations during modelling, summarises previous case studies

and links those pressures to failure possible of pipe failures.

232

SECM/13/252

COMPARING OUTCOMES OF DETERMINISTIC AND RELIABILITY APPROACHES OF

AGING REINFORCED CONCRETE BRIDGE GIRDER

1Saman De Silva,

2Amit Sagar,

3Yusufu Xiafukati

1RMIT University


2RMIT University


3RMIT University


Abstract

Bridges deteriorate with time due to change in live load; excessive usage and material degradation. At

present, deterioration of such bridges is predominantly recorded via visual inspections, which is

considered highly subjective (qualitative assessment). Later, recorded data is used for decisions, such

as; capital works program and maintenance program. Decisions made based on these recordings are

considered not having a sound scientific basis. This paper focuses to provide a mechanism which can

be applied to eliminate the subjectivity from decisions and elevate evidence based decision making.

In order to do so, a comparison is drawn between outputs of deterministic (quantitative assessment)

and reliability theories for an aging reinforced concrete (RC) bridge girder. For deterministic

analysis, a real-time theoretical simulation of flexural stresses is performed, taking into account the

age dependent behavior of shrinkage, creep (under sustained loads) and varying imposed loads.

Output of this analysis are recorded as, age dependent crack widths, which can be theoretically

estimated over the life cycle of the bridge girders. Reliability assessment is performed based on

probabilistic analysis theory, considering change in live load over time. Reliability index being

established based on the changing live load as the proof load, assuming girder had no maintenance

intervention.

Keywords: Deterministic assessment, Reliability analysis, Reliability index, RC bridge girder, Crack

width


233

SECM/13/253

A THEORETICAL STUDY OF REINFORCED CONCRETE WALLS SUBJECTED TO

ECCENTRIC AXIAL LOAD

1Saman De Silva,

2Timothy Ivanda Sanyoto

1,2School of Civil, Environmental and Chemical Engineering,RMIT University,Melbourne,Australia

Tel: 2(+61 3) 9925 3235; Fax:

2(+61 3) 9639 0138


Abstract

The increase use of precast wall panels as external and internal load bearing elements with eccentric

axial loads is evident. Most code provisions and empirically derived formulae appear to discourage

eccentricities beyond 1/6th of wall thickness by reducing the axial load carrying capacity of such cases

disproportionately or, in some cases, overestimating it. This paper examines this phenomenon

through a theoretical approach. Especially in tilt-up construction where wall panels are relatively

slender, and any vertical load transfer to the panel with an eccentricity beyond half wall thickness

seems prohibitive. However, due to construction tolerances and connection detail variations, these

high eccentric axial loads transferred from the supported structural elements such as beam, slab, or

roof purlins and rafters are common and may become problematic leading to uneconomical design.

This paper reviews international design code provisions and presents research outcomes of varying

eccentricity towards the reduction of wall axial load carrying capacity. This paper compares these

outcomes with FEA analysis outcomes as well. Walls supported on two, three, and four sides using

Finite Element Analysis methods would also be presented. Finally, a comparison between Finite

Element Analysis and code design formulae results are compared to illustrate the behavior of wall

formula and make recommendation based on the findings.

Keywords: Wall design, Reinforced Concrete Design, Finite Element Analysis, Eccentrically loaded

walls panels

234

SECM/13/254

THE IMPORTANCE OF SECURITY OF PAYMENT FOR FUTURE OF THE

CONSTRUCTION INDUSTRY IN SRI LANKA

Asanga Gunawansa


Abstract

This paper examines the reasons for the development of security of payment legislation to address the

payment related disputes in the construction industry in several common law jurisdictions and the

effectiveness of such legislation. Further, having examined the status of the construction industry in

Sri Lanka and the current regime for resolution of construction disputes, this paper draws the

conclusion that although security of payment legislation only offers temporary relief to parties

affected by payment related disputes, such legislation has the positive effect of maintaining the cash

flow, which is often considered the lifeblood of the construction industry, and thus such legislation is

a necessary tool for the future of the construction industry in Sri Lanka.

235

SECM/13/255

IMPACT OF CLIMATE CHANGE ON THE WAVE CLIMATE OF SRI LANKA

R. M. J. Bamunawala1, S. S. L. Hettiarachchi

2, S. P. Samarawickrama

3, P. N. Wickramanayake

4,

Roshanka Ranasinghe5


Telephone: +94 – 11 – 2650567 (Ext: 2115); Fax: +94 – 11 - 2651216



Telephone: +94 – 11- 2650567 (Ext: 2114); Fax: +94 – 11 - 2651216



Telephone: +94 – 11- 2650567 (Ext: 2120); Fax: +94 – 11 - 2651216


4Department of Civil Engineering, Open University Sri Lanka, Sri Lanka.

Telephone: +94 – 11 - 2881472; Fax: +94 – 11 - 2881426


5Department of Water Engineering, UNESCO – IHE, Delft, The Netherlands

Telephone: +31 15 215 17 15; Fax: +31 15 212 29 21


Abstract

Climate change and climate change driven impacts are most widely argued topics among

contemporary researches and scientists. Broadly there are two schools of philosophies that process

entirely contrasting concepts about this whole concept of climate change and its impacts. While one

of the concepts states about frequently varied climate change and occurrence of extreme weather

events the other group of philosophers are banking upon the concept of there is nothing so called a

climate change and it‟s only the indifferences in occurrence of weather and climate events. The title of

this paper itself implies the fact that this research study supports the concept of climate change and its

probable impacts, thus leaving out the other concept about climate change.Extensive concentrations of

green house gasses emitted to the earth‟s atmosphere and vast amounts of aerosols governs the

majority of anthropogenic causes for climate change, while many of the natural causes such as

changes in solar radiation also contributes immensely to earth‟s climate change.

Absence of detailed studies carried out on investigating probable impacts on wave climates due to

projected climate changes is one of the major drawbacks in handling the unique coastal echo systems

in Sri Lanka. As a country where coastal resources play a major role in its development, it is

absolutely necessary to have a convincing idea about the probable impacts that could arise on its

coastal areas. This detailed investigation provides vital information on probable impacts that might

cause on the western coast of Sri Lanka, under the influence of global climate change.

The outcomes of this study indicate that there‟s certain threat to the coasts in Sri Lanka due to a

considerable increment in mean wave height and shifted wave directions. It also indicates that not

only the number of extreme wave events increase very significantly but also its intensity upsurges in a

considerable amount as well, while indicating a time shift in seasonal variations of wave climates as

well.

Keywords: Climate Change impacts, wave climate shift, frequency of extreme wave events, mean

wave height and direction





236

SECM/13/256

PREDICTION OF STRENGTH OF SHORT CONCRETE COLUMNS STRENGTHNED

WITH FRP JACKETS: A COMPARITIVE STUDY OF DESIGN CODE EQUATIONS

1Mithila Achintha ,

2Sotira Georgiou

1University of Southampton,United Kingdom


2University of Southampton,United Kingdom


Abstract

The current paper reports selected findings from a research programme carried out at the University

of Southampton into the fundamental understanding of the effectiveness of FRP confinement, when

applied to circular concrete columns as a mean of improving strength. In this paper, predictions from

the design code equations for the axial load capacity of short circular concrete columns strengthened

with externally bonded FRP wraps is presented. By comparing predictions from the empirical

equations recommended in The Concrete Society Technical Report No. 55 (the design standard in the

UK) and ACI 440.2R-02 and ACI 440.2R-08 (the design standard in the USA) for a database of test

results of FRP strengthened concrete column specimens, the paper shows that the empirical design

equationsdo not provide accurate estimate for the failure load.To determine the axial load capacity of

strengthened columns, the governing parameter is the rupture strain of the FRP, which is easy to

define but difficult to determine. The results show that even the incorporation of the respective

observed rupture strain of FRP jackets in the design code equations do not provide better estimate for

the failure load of the columns. Furthermore, the results show that the empirical equations do not take

into account of the effects due to: for instance, low confinements in high strength concrete, different

rupture strain of different FRP materials, low rupture strain ofthick / stiff FRP jackets, and localised

FRP failures, etc. In particular, it is shown that, although predictions form the design code equations

generally agree with test results that used in the original studiesthat derived the empirical equations,

the models do not provide accurate and consistent estimates for failure load of new test specimens.

Keywords: ACI 440,Concretecolumns,Confinement, FRP, Strengthening, TR55

237

SECM/13/257

A REVIEW OFTHE PRESSURE TRANSIENT EFFECTSON WATER DISTRIBUTION

MAIN FAILURES

1J. Kodikara,

2R.M.S.U.P.Rathnayaka,

3D.J. Robert,

4P. Rajeev

1,2,3,4

Department of Civil Engineering, Monash University, Clayton Campus, Vic 3800, Australia 1E-mail:[email protected]

Abstract

This paper presents a review of pressure transient effects on water pipeline failures. Water

distribution mains in the world are becoming older and hence are experience more frequent failures.

Prediction of pipe failures become very important as the failure of large diameter pipes could lead to

high consequences of failure (economic as well as social) such as property damage, interruption to

traffic and the loss of confidence in the water utility. The most challenging task is to predict such

failures which can depend on several factors that are hard to estimate accurately. Among such factors,

internal water pressures, pipe corrosion and traffic loads andcan be paramount. Most of the failures of

large water mains reported in the literature occurred as a result of high internal water pressure acting

on corroded sections of the pipes. Hence, evaluation of steady state as well as transient pressures in

the water networkis particularly important in the process of pipe failure prediction. This paper reviews

the state of the art of pressure transient modelling to determine the failures of water mains. Relevant

failure prediction methods have also been identified to predict the failures of corroded as well as non-

corroded water pipes associated with high transient events. The use of pressure transient modelling

has been elaborated with the aid of a case study to determine the failures of corroded water pipelines.

Keywords: Pressure transients, pipe failure, water networks, corrosion, failure prediction

238

SECM/13/259

OVALIZATION MODELLING OF PIPES WITH STEEL MATERIAL: A NUMERICAL

AND EXPERIMENTAL STUDY

Asghar Vatani Oskouei1, Laya Zahedi

2, Pooya Pourshabani

3, Aydin Tamjidi

4

1Faculty of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran


2Department of Civil Engineering, Islamic Azad University, Science and Research Branch, Sirjan,

Iran.


3,4

Department of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran.

Telephone: +98-21-22970021; Fax: +98-21-22970021


Abstract

Hollow circular cross section element such as tubes or pipes has been widely used as structural

element. Therefore, its nonlinear behavior has been studied for many years. In this regard, the present

paper investigates behavior of steel pipes under an ovalizing load both in experimental and numerical

approach. Three specimens including pipes with different lengths and same diameters and thicknesses

were examined under a push test. Afterwards, the pipes were modelled by nonlinear finite element

method to compare with the experimental results. Numerical and experimental results were in good

agreement and the finite element method is appropriate in assessing this problem. Afterwards, a

parametric study was conducted on the thickness and diameter of the pipe. Results showed that by

increasing the thickness and diameter of the pipe, the strength increases, and decreases in a nonlinear

pattern, respectively. In addition, stress concentration in the pipe became critical under the loading

and support location and also two sides of the pipe.

Keywords: Steel material; Pipes; Ovalization; Numerical modelling; Buckling







239

SECM/13/260

COST EFFECTIVE PRECAST REINFORCED CONCRETE

BRIDGE DECKS FOR SHORT SPANS

G Ramanan1,M.T.R. Jayasinghe

2

1G Ramanan, Department of Civil Engineering, University of Moratuwa

2M.T.R. Jayasinghe, Department of Civil Engineering, University of Moratuwa


Abstract

Sri Lanka has so many waterways due to it being a tropical country with reasonably high rainfall. Sri

Lanka also has a very high road density. The total number of km of the road network consisting of A,

B, C, D and E class roads exceeds 100,000 km. In many of these C, D and E class roads, there would

be a need for bridges of small spans such as 5-10 m. In such situations, it is useful to have well

developed cost effective systems.

One such system has been developed using precast beams and precast slab panels. The design

philosophy and the practical implementation has been described in detail in this research paper. This

bridge has the potential to reduce the cost of construction by up to 50% from the cost of a typical

solution while ensuring adequate load carrying capacity and durability in a country with relatively

lower labour costs. This can be considered as a sustainable solution as well since this innovative

solution can minimize the usage of key construction materials for any small span bridge decks such as

concrete and steel. Due to its simply supported behaviour and light weight, it would be possible to

use simple foundation systems that may be allowed undergo a certain amount of settlement due to

consolidation while not affecting the behaviour of the deck very much.

Keywords: precast reinforced concrete, bridge decks, crack controlling

240

SECM/13/261

ACHIEVING DISASTER RESILIENCE THROUGH THE SRI LANKAN EARLY WARNING

SYSTEM: GOOD PRACTICES OF DISASTER RISK REDUCTION AND MANAGEMENT

Shayani Weeresinghe

1 ANDROID Disaster Resilience Network, Department of Civil Engineering, University of Moratuwa,

Sri Lanka.

Telephone: +94 777 271 069


Abstract

A case study report of the good practices of the Sri Lankan Early Warning System, it scrutinises its

components; infrastructure, risk knowledge (i.e. hazard, vulnerability and risk assessment),

preparedness and early warning dissemination, disaster response and coordination and ultimately

leading to measures to achieve disaster resilience. The objective was to highlight good practices,

identify gaps and useful recommendations within an up-to-date context to promote disaster resilient

local and national governance. It concludes with development projects in Sri Lanka which have

successfully integrated disaster risk.

Keywords: Disaster Risk Reduction, Disaster Resilience, Preparedness, Early warning

dissemination, Risk Assessment

241

SECM/13/262

INNOVATIVE EARTH RETAINING SYSTEMS ADOPTED AT THE PRINTING COMPLEX

PROJECT FOR AITKEN SPENCE (PVT) LTD. AT MAWARAMANDIYA

1Shiromal Fernando,

2Damian Neomal Ferdinando

1Civil and Structural Engineering Consultants (Pvt) Ltd

Tel: +94-11-2683979,Fax: +94-71-8802859


2Civil and Structural Engineering Consultants (Pvt) Ltd


Abstract

Retaining earth is a predominant requirement in sloped land constructions. Holding back the soil mass

in the most economical and efficient manner while preserving constructive areas at required levels for

intended developments is the main objective of any earth retaining system. Gravity walls, cantilevered

walls, sheet pile walls and anchored walls are commonly used to stabilise slopes. In addition to these

conventional methods soil nailing, gabion walls, stabilization with artificial reinforcement, etc are

increasingly used in modern constructions. However, selection of the most appropriate system to

resist the lateral earth and hydrostatic pressure and/or to stabilize the slopes depends on several factors

such as the retaining height, available area, properties of soil to be retained, cost of construction, etc.

The land selected for the construction of the factory is located in an undulant terrain. Thus it requires

earth retaining both along the site boundary and at intermediate locations within the premises. The

heights to be retained are in the range of 1m to 7m. A few distinct systems including anchored gravity

walls and soil nailing were innovatively adopted at different locations as appropriate, depending on

the height of the slope to be retained, space availability and cost considerations. This paper discusses

the design aspects and modifications adapted to the conventional design and construction procedures

of soil nail retaining systems, possible alternative configurations and other earth retaining methods

implemented at the site. The paper also includes recommendations and precautions to be taken with

the specified soil nailing system, a cost comparison between conventional gravity walls and

cantilevered RC walls.



242

SECM/13/263

STRUCTURAL BEHAVIOUR IMPROVEMENT BY PARTIAL REPLACEMENT OF

CEMENT USING VARIOUS PRODUCTS

J.Divya Johns1, S. Judes Sujatha

2

1University College of Engineering, Konam, KaniyaKumari, TamilNadu, India – 602 105

2University College of Engineering, Konam, KaniyaKumari, TamilNadu, India – 602 105

Telephone:09487611185


Abstract

In the past few years many researches are carried out in concrete for improvement in strength

and reliability. Generally the major element cement is replaced by adding a partial proportion of

naturally and abundantly available elements which has the ability to vary the physical property.

Adding these materials may causes some positive results like increase in compressive strength, tensile

strength and workability of concrete etc. So the improvement in physical property of concrete depends

on proper selection of replacement materials and its exact ratio.

In this Paper, experimental work has been done for studying the effect of silica fume, fly ash and

Meta kaolin by partial replacement for cement in terms of improved performance of compressive

strength, tensile strength, flexural strength and durability of concrete. The property improved

Concrete specimen were tested and compared with plain concrete specimen at different age. Initially

the mix design of M30 grade concrete was made of different materials with various percentages

ranging from 5%, 10%, 15%, 20%, 25% and 30%. Then for these mix design of concrete, different

samples like beams, cylinder and cubes are casted. These samples like beams, cylinders and cubes are

tested in compressive testing machine and Universal testing machine for compressive strength

conducted in 7, 28 days. Also the flexural strength and tensile strength has been found after 28 days.

Keywords: compressive strength, tensile strength, flexural strength, workability and durability, silica

fume, fly ash and meta kaolin


243

SECM/13/264

EURO CODES FOR DESIGN OF PRE-STRESSED CONCRETE HIGHWAY BRIDGES-

A REVIEW FOR HIGHWAY LOADINGS

S.Seyanthan, M T R Jayasinghe





Abstract

Sri Lanka is a country with relatively high road density and also with tropical climatic conditions that

cause high rainfall intensity. Therefore, there are so many bridges of various spans in these roads.

With many bridges constructed or rehabilitated, there is a need to be precise with the design concepts

to achieve a significant economy when constructing and maintaining the bridges. With the adoption of

Euro codes as the design standard in many countries, there is a need to adopt such standards instead of

British standards that are currently used since BS standards will not be updated in future. This paper

describes some important findings that would be of high significance for the bridge engineers in their

change over to Euro codes with the types of decks that are commonly used in Sri Lanka and also

probable structural forms that can be adopted in future. In this research paper, the attention has been

on the adoption of various loading conditions and the desirable modifications that could be

recommended for various classes of roads as for the classification adopted in Sri Lanka.

Keywords: Highway loading, Euro code, M Beams, Y Beams


244

SECM/13/265

APPLICATION OF COMPUTATIONAL FLUID DYNAMICS (CFD) IN WIND ANALYSIS

OF TALL BUILDINGS

Damith Mohotti1, Priyan Mendis

2, Tuan Ngo

3

Department of Infrastructures Engineering, The University of Melbourne, Victoria, Australia

Telephone: +61425531977


[email protected],

[email protected]

Abstract

Computational Fluid Dynamics (CFD) has wide range of applications in modern engineering

community. Use of CFD in wind engineering has significantly increased over the last few decades.

However, very limited work has been done on the application of CFD in simulating the wind

behaviour around tall structures. With the development of high speed supercomputers, the possibility

of performing such analysis within reasonable time period has become a reality. This paper presents

an outline of such study performed using an advanced finite element (FE) code. An isolated

rectangular building model has been considered as the based model in the analysis. A constant

velocity profile has been used with k-ε turbulent model. An atmospheric boundary layer based wind

profile has been adopted using a user defined function in the simulations. The effect of neighbouring

buildings onto the nearby tall building has also been discussed. Wind pressure development, velocity

profile in the close vicinity of the building was studied and presented.

Keywords: Computational Fluid Dynamics, wind loading, tall buildings.




245

SECM/13/266

DUCTILITY DESIGN OF HIGH-STRENGTH REINFORCED CONCRETE COLUMNS FOR

SUPER-TALL BUILDINGS

K.B.K. Shanaka1, Priyan Mendis

2, Tuan Ngo

3

Department of Infrastructures Engineering, The University of Melbourne, Australia

Telephone: +61450515484


[email protected],

[email protected]

Abstract

Design and construction of super-tall buildings have become a current trend in the Civil Engineering

industry discipline due to land scarcity in the metropolitan areas caused by the rapid urbanizations.

Using high-strength (50 to 100 MPa) and very high-strength concrete (>100 MPa) (HSC) columns for

tall buildings, has accepted to be structurally and economically viable and also make the columns

more efficient and durable. Codes around the world do not address the design of high-strength

columns, especially very high-strength range, accurately. This research paper discusses the ductility

of HSC columns and compares the ductility design provisions of current guidelines and research

findings. The paper also addresses the required complementary guidelines for the ductility design of

HSC for super tall building applications.

Keywords: High-Strength Concrete, Ductility, Confinement, Columns



246

SECM/13/267

MODELLING THE COMPRESSIVE STRENGTH OF NANO-SILICA CEMENT

COMPOSITES

Madhuwanthi Rupasinghe1, Thushara Priyadarshana

2, Priyan Mendis

3, Ranjith Dissanayake

4,

Massoud Sofi5

1Department of Infrastructure Engineering, The University of Melbourne, Australia

Telephone: +61 3 83440193


2Holcim, Srilanka.



Telephone: +61 3 83447244 ; Fax: +61 3 83444616


4Department of Civil Engineering, The University of Peradeniya, Srilanka.

Telephone: +94 777 809895; Fax: +94 814476797




Abstract

Nano-technology and nano-materials have proven to be influential on sustainable development and

overall competitiveness of the construction industry. Better understanding and engineering of

materials at nano-meter scale can result in novel construction materials which are stronger and more

durable than conventional materials. Concrete is the most widely used construction material and has a

significant impact on material and energy sources worldwide. Engineering concrete at the nano-meter

scale includes the incorporation of nano-sized particles into concrete at suitable proportions and

methods. Nano-silica is one such nano-material, which can be integrated into concrete with the aim of

improving overall properties. Due to the rich SiO2 content, nano-silica acts not just as a filler, but also

as a pozzolanic material within the mix.

This paper focuses on the effects of replacing the cement content of mortar with nano-silica at small

replacement levels. In the numerical analysis, existing models for cement hydration are altered

suitably to implement the effects of nano-silica on the cement hydration process. Finite element

analysis along with homogenisation principles are used to predict the compressive strength of mortar.

An extensive experimental program was carried out to find the effects on compressive strength of

mortar when the cement content is replaced with nano-silica for small replacement levels, and the

results are used to validate the proposed numerical model.

Keywords: Nano-silica, mortar, concrete, compressive strength






247

SECM/13/268

EARLY-AGE STRENGTH DEVELOPMENT OF FLY-ASH BASED CONCRETE

M. Sofi., E. Lumantarna, P. Mendis, B. Fiske, D. Hagebols, J. Dwyer, T. Gunawardena

Department of Infrastructure Engineering, University of Melbourne.

Telephone: +66383447244

E-mail: massoud@ unimelb.edu.au

Abstract

As global pressures continue to mount to decrease CO2 emissions, the responsibility of the concrete

industry to decrease their carbon footprint continues to grow. In order to reduce cement production

and use, supplementary cementitious materials, such as fly ash are often added to concrete. The use of

fly ash in concrete exists for many reasons, including reduced costs, improvements in workability of

fresh concrete, reductions in initial concrete temperature rise, reduced expansion and increased

durability. However, its application is limited due to concerns with the early-age strength

development of fly ash based concrete. This is important for many applications including post-

tensioned concrete and precast construction. Also there is a concern that early-age strengths are

affected by the source of fly-ash. This paper presents results of an experimental program aimed at

determining the early-age strength performance of Gladstone and Vales Point fly ash when used as a

cement replacement in concrete. These are the two common fly ashes currently in use by the concrete

industry in Australia. A regression analysis was undertaken in order to determine equivalent strength-

maturity functions. It was found that the strength-maturity functions can be used to represent the

strength development behaviour of fly ash based concrete at early ages. The comparisons of the

results show that Gladstone fly consistently yields better early-age compressive strength results than

Vales Point fly ash.

Keywords: fly-ash, early age concrete, compressive strength, maturity



248

SECM/13/269

FRAMEWORK FOR USING RECYCLED CONCRETE AGGREGATE IN READY MIX

CONCRETE PLANTS

Mayuri Wijayasundara1, Priyan Mendis

2, Massoud Sofi

3

1Department of Infrastructure Engineering, The University of Melbourne.

Telephone: +66383449696



Telephone: +6638344 7244



Telephone: +6639035 8472


Abstract

Recycled concrete aggregate (RCA) produced from construction and concrete waste (CDW) is

presently used as a road base material in Australia. While the scarcity of natural aggregates (NA) as

an extracted material has increased the demand for alternative materials used in manufacturing of

concrete, the use of RCA in structural concrete closes the recycling loop and improves the Green Star

Rating prospects of concrete structures. With these two-fold advantages, use of RCA as a structural

material has gained increased importance in the recent years. While the technical aspects of recycled

aggregate concrete (RAC) such as replacement rates with NA concrete (NAC), strength and

mechanical properties of RAC have been covered in the literature, there is a lack of information on

how the process of replacement will affect the well established concrete plants and their operations.

This paper considers the opportunities, challenges and the impact of manufacturing RAC when

replacing NAC in the ready mix concrete industry. The paper analyses the required response of the

ready-mix concrete industry, recycling and quarrying industries and proposes an integrated conceptual

framework for the manufacturing of RAC at industrial scale. The proposed framework presents a

methodology for analysing the feasibility of establishing the total supply chain for RAC.

Keywords: Recycled concrete aggregate, recycled aggregate concrete, ready mix concrete, plants







249

SECM/13/270

EARTHQUAKE ANALYSIS OF A TYPICAL TALL BUILDING IN SRI LANKA

Priyan Mendis1, Nilupa Herath

1, Shiromal Fernando

2, Dilina Hettiarachchi

2, Bhathiya Waduge

2

1 Department of Infrastructure engineering, The University of Melbourne

Telephone: +61383447244


2 Civil & StructuralEngineering Consultants Private limited, Sri Lanka

Abstract

Sri Lanka is located in a low-seismic region and numbers of small scale earthquakes have occurred in

the island in the past. Because these earthquakes occurred have been rare in Sri Lanka, not much

interest is given for earthquake analysis of structures in structural design, although some earthquake

detailing guidelines have been proposed in the past. However these design philosophies need to

change as experts have predicted more frequent seismic activities in the future, in Sri Lanka and Sri

Lanka may even be classified as a low-to moderate seismic region. With the development of tall

buildings around the capital city of Colombo, there is a need to identify and develop an accurate

method for seismic analysis of structures for Sri Lankan soil conditions. In this study, a generation of

simulated earthquakes for Sri Lankan soil conditions is presented. A case study structure is analyzed

for the proposed simulated earthquakes and results are presented.

Keywords: Seismic analysis, Tall buildings, response spectrum



250

SECM/13/271

DEFLECTION RELATED SERVICEABILITY ISSUES IN STEEL BUILDINGS WITH

LARGE SPAN GIRDERS

1N. Abeysuriya,

2M. T. R. Jayasinghe

Department of Civil Engineering,

University of Moratuwa, Moratuwa, Sri Lanka


Department of Civil Engineering,

University of Moratuwa, Moratuwa, Sri Lanka


Abstract

The usage of steel as a structural material has been gaining popularity in the recent years in Sri Lanka.

Since the construction with reinforced concrete is of relatively lower cost in Sri Lanka, steel can

become competitive only if special applications could be promoted.

One such aspect is the speed of construction and another is the ability to span over larger distances

due to light weight. However, such long spans create special serviceability related issues that would

warrant special attention. One such issue occurs when masonry walls that are used as partitions are

supported on the long span girders. In Sri Lanka, solid masonry wall partitions are considered as a

need by the clients when they construct hotel buildings due to various issues that could arise with dry

wall construction primarily due to the cost, hot humid environment and the durability issues. The

weight of the masonry could give rise to greater deflection and hence could demonstrate a higher

possibility for creating cracks. Another problem is the shrinkage related cracks that could be induced

in the ends of the walls along with thermal related cracks when the masonry walls are exposed as in

the case of external walls. All these cracks could be problematic for the structural engineer since all

these cracks have to be repaired to ensure acceptable level of serviceability. Hence, various

techniques that could be used to minimize the cracks in masonry either following the code based

guidelines for deflection or devising special guidelines is a desirable approach that should be adopted

by the structural design engineer. This research is aimed at identifying and solving such important

issues that could otherwise impair the performance.



251

SECM/13/272

TOLL GATES AND TOLL BUILDINGS IN SRI LANKA

1D.S. Hettiarachchi,

2P. Mendis,

3W.J.B.S. Fernando,

4B.D. Waduge

1Civil & Structural Engineering Consultants, Sri Lanka.

Telephone: +94 71 324 2414;


2Department of Infrastructure Engineering, University of Melbourne, Australia.

Telephone: +61 41 931 2481; Fax:+61 3 83444616



Telephone: +94 71 421 6681;



Telephone: +94 71 447 6106;


Abstract

Sri Lanka, also known as the pearl of the Indian Ocean declared open its first expressway in

November 2011 and it‟s second in October 2013. Expressways help to boost the economy of the

country by reducing travel times and by providing increased opportunities for business. To cater the

main requirements and functionalities of these expressways, toll gates and toll buildings play a vital

role.In both ofthe expresswaysconstructed, it can be noted thatthe main architectural features

embedded to toll gates and buildings were inspirational concepts adapted from traditional Sri Lankan

timber structures/monuments found in Bogoda Bridge in Badulla, the pillars in Embekke Devalaya,

Pekada and Ambalama.

Despite the architectural characteristics of these structures, the main feature of these

constructedstructureswas construction being made with the use of off-formed reinforced concrete.

Another key feature that can be highlighted is the types of foundations used in both occasions. Due to

marshy land conditions precast piles were driven during the construction of the Colombo -

Katunayake Expressway and shallow footings being used in the Colombo - Matara expressway. Toll

gate structures possess large cantilevers, thinner beams, slender columns and off-formed finishes.

Thus, elements were heavily reinforced and self-compacted concrete being used to construct these

elements. This paper presents on how traditional architectural features ofSri Lankan timber structures

have influenced the design of toll buildings and gates of the Colombo - Katunayake and Colombo –

Matara expressways.

Keywords: Expressway, Toll gates, Toll buildings, Architectural characteristics







252

SECM/13/273

OLD AND NEW IN SRBSN (SINTERED REACTION BONDED SILICON NITRIDE)

Hai-Doo Kim

Korea Institute of Materials Science

797 Changwondaero, Seongsan-gu, Changwon, Gyeongnam 642-831, Korea


Abstract

Silicon nitride is one of the best ceramic materials with many useful properties, however, actual

application is limited mostly due to its high production cost. Use of silicon powder instead of

expensive silicon nitride powder is, therefore, attractive. The development history of RBSN and

SRBSN as well as the pros and cons of SRBSN will be reviewed.

Dense SRBSN(sintered reaction bonded silicon nitride) ceramics with high strength and toughness

was obtained by modifying the structure of RBSN followed by the high temperature gas pressure

sintering. Optimization of gas pressure sintering and hot pressing conditions were investigated by

modifying the heating and pressurizing schedule.

A fraction of fine silicon powder was added to modify the structure of RBSN after nitridation.

Addition of fine silicon powder to coarse silicon powder leads to the early onset of phase

transformation and sintering, which lowers the post sintering temperature to give full densification.

Microscopically, addition of fine silicon powder generates fine silicon nitride grains after nitridation,

which gives rise to the fine pore structure. During intermediate temperature range of post-sintering

process the newly generated fine silicon nitride grains leads to the enhanced phase transformation and

densification. The resulting microstructure after post-sintering is such that the matrix grain size is

smaller than the conventional case without fine silicon addition. 10% addition of fine silicon powder

to the silicon powder compact with 8% Lu2O3 and 2% SiO2 system showed near TD when sintered at

1850°C with high fracture strength of above 900 MPa. The addition of fine silicon is effective up to

30%.

The fracture toughness values measured by DCB method show the range up to 9MPa▪m0.5

,

whichishigherthanconventionalcasewithoutfinesiliconaddition,whichispossiblyduetothemodifiedmicro

structure.

The conditions to give porous microstructure with acicular grains was investigated in sintered RBSN

in order to modify the pore structures. The efforts were made to enlarge the average pore size of

porous SRBSN to reduce the pressure drop of the SRBSN filter. SRBSN DPF filter shows better

trapping efficiency of PM compared to commercial cordierite filter. Especially SRBSN filter shows

better trapping efficiency for nanosized PM possibly due to the smaller pore size with minimum

pressure drop compared to the commercial cordierite filter. Future works to be done in SRBSN will be

explained and future possibilities and directions will be discussed.

253

SECM/13/274

REPAIR OF LARGE DIAMETER CAST IN-SITU CONCRETE PILES

1S. Dharmasena,

2W.J.B.S. Fernando

1Nawaloka Piling, Sri Lanka.

Telephone: +94 77 748 5050



Telephone: +94 71 421 6681;


Abstract

The construction industry in Sri Lanka has seen a rapid boom in the past decades with major

developments such as, new sea ports, aviation hubs and infrastructure taking place all over the

country. Due to the varying soil conditions, and resource availability; Geotechnical experts quite often

recommend bored and cast-in-situ piles as the deep foundation of choice in such cases.Although

thequality control and quality assurance methods or systems for piling have developed in par with the

increasing piling construction works, many soft toe failures are reported in the resent past.

Pile failure is a very costly lost monitory and cause project delays to the Contractor. This paper

discussessuccess stories of the pile repair techniques which authors are directly involved. The repair

of large diameter cast in-situ concrete piles is done using cement grouting.

Keywords: Large diameter concrete piles, cement grouting, soft toe




254

SECM/13/275

INCREASING THE FLEXURAL STIFFENESS BY THE INTRODUCTION OF STEEL

SECTIONS EMBEDDED IN CONCRETE

W. J. B. S. Fernando1, K. H. D. Nayantha

2

1Director, Civil and Structural Engineering Consultants (PVT) Ltd.

Telephone: +94-11-2683979; Fax: +94-71-8802859


2Postgraduate student, Department of Civil Engineering, University of Moratuwa.

Telephone:+94-77-375 7741


Abstract

The demand for unobstructed spaces in the modern buildings requires beams having longer spans.This

results in deeper cross sections reducing the headroom of the particular room which is undesirable by

the occupants and the architects. Even though the depth of the section can be reduced by introducing

the higher amount of reinforcements, high reinforcement area / concrete area will prevent the flow of

the concrete through densely reinforced locations creating honeycombs in the element.

This paper presents the method adopted in designing a slab supporting system where the beam depth

had to be reduced up to the thickness of a slab. Three alternatives; concrete section with maximum

amount of steel in the section, steel I section and a composite section consisting with a steel I section

embedded in concrete were analyzed to come up with the solution.

The concrete section with maximum amount of steel failed in the criteria of client‟s requirement and

the steel I section failed in the criteria of the excessive deflection. The solution found was to have

steel I section embedded in concrete which had a higher flexural strength and the stiffness compared

to other two alternatives.

Keywords: Composite Section, Encased Steel Section.



mailto:E-mail


255

SECM/13/277

INVESTIGATION OF IMPACTS OF HIGHWAY AND ROAD CONSTRUCTION ON

SURFACE WATER QUALITY

N.P.Miguntanna1, A.W.N.Abewickrema, R.W.M.Amanthika, A.L.T.M.Abeysinghe, R.K.Tennakoon

1 Department of Civil and Infrastructure Engineering, Faculty of Engineering, South Asian Institute of

Technology and Medicine (SAITM), Sri Lanka.


Abstract

The water quality and land use are inextricably entwined. This paper describes the outcomes of a

research project conducted to understand the impacts of highways and roads construction and

development projects on surface water quality. The outcomes of the research project aims to integrate

into the planning, design and operational stages of the highways and roads construction and

development projects to safeguard the water quality of the natural water bodies adjacent to the

construction sites.

The water quality data for pH, Electrical Conductivity (EC), Total Suspended Solids (TSS),

Escherichia Coli (E. coli), Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO) of surface

water samples collected at adjacent water bodies of several highway and road construction sites in Sri

Lanka were used.The study strongly recommends the importance of implementation of both structural

and non structural Best Management Practices (BMPs) and establishing strong policy frame work for

all highway and road construction and development projects must adhere to minimize the adverse

impacts of construction activities on the water quality of adjacent water bodies. Furthermore, detail

understanding on gradation of solids build-up on roads, the adherence of pollutants to different

particles sizes of solids and consideration of different geographical and surface characteristics is of

crucial importance for effective design of BMPs. In addition, pH and TSS can be used as good

surrogate indicators of the surface water quality.

Keywords: Water Quality, Highways and Roads Construction, Best Management Practices

256

SECM/13/278

A MODEL FOR TEMPERATURE DEPENDENT TENSILE STRENGTH OF GRAPHENE

M.A.N. Dewapriya1, R.K.N.D Rajapakse

2

1School of Engineering Science, Simon Fraser University, Canada.


2School of Engineering Science, Simon Fraser University, Canada.

Telephone: +01 (778)-782 3826; Fax: +01 (778)-782 5802


Abstract

Quantized fracture mechanics is a recently developed energy based fracture theory, which substitutes the

differentials in Griffith‟s energy balance criterion with corresponding finite differences while taking into

account that cracks propagate in a discrete manner at the nanoscale. We compare ultimate tensile strength of

graphene given by quantized fracture mechanics theory and Griffith‟s energy balance criterion with

molecular dynamics simulation results. This comparison reveals that quantized fracture mechanics is more

accurate compared to Griffith‟s criterion in estimating ultimate tensile strength.

In view of the good agreement between molecular dynamics and quantized fracture mechanics results, it is

required to estimate ultimate tensile strength of a pristine graphene structure at different temperatures in

order to apply quantized fracture mechanics concept at various temperatures. Ultimate tensile strength of a

pristine structure is not available at arbitrary temperatures. In order to overcome this problem, we propose a

novel kinetic model which combines quantized fracture mechanics with Arrhenius formula and Bailey‟s

principle. The proposed model can be used to estimate fracture strength of graphene at various temperatures

using only the stress-strain relationship at a certain temperature. A comparison with fracture strength of

graphene given by molecular dynamics simulations at various temperatures confirms the accuracy of the

proposed kinetic model.

Keywords: Graphene fracture, Quantized fracture mechanics, Griffith’s criterion, Molecular dynamics,

Kinetic analysis



257

SECM/13/279

DEVELOPING A DISPERSION MODEL FOR INDOOR VOC FOR ENAMEL PAINTS

1G.D.V.M. Wijewickrama,

2C. Jayasinghe,

3T.M. Perera







Abstract

Volatile Organic Compounds (VOCs) are emitted from various solids and liquids which are used in

day to day domestic activities. Some of them are having adverse health effects but still people use

certain products which emits such VOCs unconsciously. The most common VOC sources in a house

are paints, lacquers, carpets, pesticides, cleaning agents and air fresheners. But finding the respective

indoor pollutant effects will have a higher experimental cost. Hence occupants ignore the effects of

VOC exposure by neglecting the gravity of the health problems. Therefore suitability of using a

computer model to predict the air pollutant dispersion in an indoor environment with a proper

validation from an experimental data set has been carried out in the research covered in this paper.

Keywords: Dispersion Model, VOC, Enamel Paints, Indoor Air Quality



258

SECM/13/280

A FULLY INTEGRATED DESIGN OF A MIXED USE MEGA PROJECT IN COLOMBO,

SRI LANKA – KRRISH SQUARE

A.R. Hira1, K Mukherjee

2, S. Mooney

3

1Buro Happold, London, UK

Telephone: Number +912233414133


2Buro Happold, Mumbai, India



3Buro Happold, Mumbai, India


E-mail: Sean. [email protected]

Abstract

In the last five years the sub-continent has commenced its appetite to join many other countries around the

world to construct genuine tall buildings to satisfy the region‟s impressive economic growth and the

corresponding unprecedented urbanization that is expected over next few decades. Colombo, the financial,

commercial and political capital of Sri Lanka, is not expected to escape from this Asian trend. This

combined with the extraordinary increases in urban land prices has and will lead to the growth of tall

building construction in the region. Whilst in many of the other countries the evolution of tall building

construction has spanned over several decades, in the case of US nearing a century, the sub-continent is

experiencing the challenge of building super tall buildings with heights over 300m with a history of only

several years. With such a short history, the industry faces many challenges as many of the decisions,

including design, costing and construction technology, for current tall buildings are made on the basis of

extrapolating the decisions applied to 10 to 20 story buildings. This inevitably can lead to a financially

unsustainable development fraught with many short and long term difficulties.

Colombo is about to receive its first mega project in the heart of its CBD. The project is a genuine mixed

use development comprising of “A” class office space , prime residential occupancy, 5 star hotel

accommodation, a substantial retail space to support the development and the ever increasing tourist and

middle class population occupying the city and car parking facilities. The development comprises of three

super-tall towers with a common podium/basement occupying the whole island site which is encircled by a

busy multi-lane roadway. The feature element of the project is the 400+m tall mixed use iconic tower

representing Sri Lanka‟s rapid transition into becoming a major economical force in the region over the next

few decades.

Buro Happold are the consulting engineers for the overall project responsible for the Structural and MEP

services for the project. This paper will outline the evolution of the design of the project, with emphasis of

the tower elements, identifying the importance of an integrated design approach during the early stages of

design for complex super-tall projects. The significance of identifying structural considerations and the

importance of accommodating the Structural and MEP demands and Vertical Transportation into the

architectural design of the project is discussed to ensure that the project is buildable within acceptable time

frames and is financially viable.

Keywords: Supertall Buildings, Mixed Use, Colombo-Sri Lanka, Integrated Design





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