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PROJECT REPORT

ON

COMMON DEFERCT

IN

BUILDINGCONSTRUCTIONAND

REMDIAL MEASURES

PRESENTED BY:

S.K. SHARMA XEN/BR/NWR

R.MURALI AXEN/Works/SR

L.N. REDDY ADEN/SCR

K.K. SINGH ADEN/NFR

IN THE GUIDANCE OF:SHRI. N.C.SHARADA Sr. PROFESSOR

IRICEN, PUNE


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1. PREAMBLE

Importance of Housing

Housing is an important scale of the level of countrys socialprogress. Besides food and clothing humans next basic need is shelter.

Shelter they requires for protecting himself against natural calamities, wild

animals and beasts and from other fellow beings. The history of mankind

reveals that the man has been moulding his environment consciously or

unconsciously throughout the ages. From the cave his early abode down

to the most sophisticated air-conditioned houses of today, it is an absorbing

and thought-provoking study of humans progress and advances in various

fields.

House is a medium for self expression as well as a sanctuary for old age.On an average, one lives almost two-thirds of ones life in the house. As

such, ownership and utility of house contributes a lot to human welfare and

joy. In India particularly, the very possession of house is regarded as a

symbol of prestige and status in society. The house ownership inculcates a

feeling of responsibility by society about use, poise and belonging to a

community of people. Voltaire had rightly said that ownership gives

personality and uplifting pride. House ownership binds one to the soil, to the

community, ennobles, and creates self-confidence, dignity, a sense of

responsibility, security, civic sense and stable personal behavior. It is notuncommon that to acquire this objective, the people put all efforts and hard

earned savings towards this end.

Housing building design which includes its internal and

external environment has traditionally been the responsibility of the

architect. With recent developments house building has now become so

complex a task that, except for the simplest of buildings, a multi-disciplinary

involvement is necessary. Internal form and environment will be determined

by the functional requirements of the occupants, the space needed to meet

these functional requirements and the required comfort levels in regard tosuch items as noise, temperature, humidity and lighting. The external form

and environment depends upon the site characteristics and adjacent

buildings.


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Housing Organizations and Associations

In India, general requirements for planning and layout of

buildings have been covered by the relevant by laws brought out by the

local authorities in various big cities of different states. All these by-lawsmore or less follow in principle the by-laws laid down by the Indian

Standard Institution in IS : 1256and the National Building Code Part II

Administration, Part III General Building Requirements, Part IV Fire

Protection, Part VIII Building Services, and Part IX Plumbing Services.

In India, four organizations dealing with various aspects of

housing are functioning under the aegis of the Ministry of Works and

Housing, namely, National Building Organisation, National Building

Construction Corporation Limited (N.B.C.C). Housing and Urban

Development Corporation ( H.U.D.C.O), and Hindustan Housing Factory (H.H.F).

Central Building Research Institute

The Central Building Research Institute is essentially a

research body set up by the Council of Scientific and Industrial Research.

This National Institute was established in the year 1951. this work of the

Institute is organized in seven research divisions, viz (1) Building Materials,

(2) Soiling Engineering, (3) Efficiency of Buildings, (4) Building Process,Plant and Productivity, (5) Architecture and Physical Planning, (6) Fire

Research, and (7) Rural Building.

The last two have been added in the last. Besides these,

there is also a division of information and extension to look after the

research needs of the scientists and to assist in the utilization of the results of

research.


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2. INTRODUCTION

In Railways yearly around Rs. 1200 crore spend for the construction

of New Buildings, bridges and Roads. In addition to that for maintenance of

exgissiting structures lot of amount spend on every year, but properplanning, supervision, good quality of raw materials and skilled

workmanship not ensured at the time of construction which leads to lot of

construction defects, thus makes perennial problem to maintenance of

Railway Buildings.

Practically no supervision available at the time of Building construction

work, in most of the Railway work spot, it is left to choice of contractor to

choose the raw materials and to decide labour workmanship.

Most of the Labour engaged by contractor is not suitable to carry out the

work, and not having adequate experience in the work entrusted to them.

Due to construction boom in private sector skilled labours are not

available in market, so forced to compromise with semi-skilled/unskilled

labours.

In this Project we made small attempt to bring out the some of the most

common defects noticed in Railway Building construction works spots, it is

not to find a fault in any individual but to improve the system of work andto achieve safe and maintenance free Buildings in Railways.

3. BUILDING CONSTRUCTION IN RAILWAY

Indian Railways has large number of buildings for its various

infrastructural needs, viz., service buildings, staff quarters, passenger

amenities, etc. At present more than 7000 station buildings, many types of

passenger amenities, and approximate six lakhs staff quarters are available to

meet with daily requirement of about 15million passengers and

14lakhs railway employees

The construction of these buildings was started at the time of

introduction of railway system in India and still continued along with the

extension of railway network in the India. Initially most of railway building


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were constructed in stone masonry/ brick masonry in lime mortar with tiled

roof or jack arch terracing etc. afterwards with the production of cement in

India, construction started with stone masonry/ brick masonry in cement

mortar along with RCC roof slabs. Many of the old buildings have given

aesthetically pleasing look and historical heritage look as per that area and

are landmarks even today. The service life of a building is expected more

than 50 years with normal maintenance.

Indian Railway has a big building infrastructure but no due care is

being given for the building construction and their maintenance which is

resulted in poor construction and quality work.

We in the Railway far behind from other department as well as from

open market in the building construction because very casual approach is

being taken in Railway for construction/maintenance of buildings.

To look after building construction works in open line, the

administrative set up are CE/Works at zonal level available, at divisional

level Sr.DEN/DEN, sub-divisional level ADEN and field level SSE/SE/JE

(Works) are responsible.

4. What are Construction Defects?

Although there is controversy in defining what construction defectsare, normally it is grouped into four categories.

a). Design Deficiencies:Design deficiencies, which sometimes stemfrom the work of engineers. These design professionals design a building or

design a specific system that does not function, as it was intended to

function. The end result is a product that is defective.

b). Material Deficiencies: Material deficiencies are occurring by usinginferior building material that causes a variety of defect. This type of defect

that is fairly common is doors and windows built with poor quality materials

will warping and cracking.

c). Substandard Workmanship:This category of construction defectusually becomes evident with water seepage through some part of the

building structure. Other examples of such as cracks in floor slabs or in the


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foundation. There could also be evidence of construction deficiencies in

plumbing.

d). Subsurface or Geo-technical Problems:This issue occurs when

housing developments are built in areas where water once stood, or is hilly,both resulting in an unstable foundation upon which to build a house. If

foundation not did properly on this soil then inevitably it will begin to see

symptoms of this construction defect.

In this project we had taken up last three defects for discussion and

left design aspect deficiencies.

5. CRACKS IN THE BUILDING

Occurrence of various crack patterns in the building during

construction, after completion when it is subjected to super imposed load or

during the service life, is a common phenomenon. A building component

develops cracks whenever the stress in the components exceeds its strength.

Stress in the building component could be caused by externally applied

forces, such as dead, live, wind or seismic loads; foundation settlement etc

Cracks in buildings could be broadly classified as structural and non

structural cracks.

Structural Cracks:- These occur due to incorrect design, faultyconstruction or overloading and these may endanger the safety of a building.

e.g.Extensive cracking in wall and beams.


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Non Structural Cracks:- These are mostly due to internally induced

stresses in buildings materials and do not endanger safety of a building but

may look unsightly, or may create an impression of faulty work or may give

a feeling of instability. In some situations due to penetration of moisture

through them non structural cracks may spoil the internal finishes thus

adding to the cost of maintenance, or corrode the reinforcement, therebyadversely affecting the stability of the Structural in long run.

e.g. Plastering cracks, Vertical crack in a long compound wall due to

shrinkage or thermal movement etc.


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6.PRINCIPAL CAUSES OF CRACKS

To prevent or minimize the occurrence of non-structural cracks it is

necessary to understand the basic causes and mechanism of cracking, andcertain properties of building materials which may lead to dimensional

changes of the structural components. The principal mechanism causing

non-structural cracks in the building are:

a). Moisture change b). Thermal movement

c). Elastic deformation d). Creep

e). Chemical reaction f). Foundation movement & settlement of soil

g). Growth of vegetation

a) Moisture change:Most of the building material (e.g. Concrete, mortar, burnt clay brick, timbe

plywood etc.,) are porous in their structure in the form or inter molecular shrink

on drying. These movements are reversiblei.e. cyclic in nature and are caused b

increase or decrease in the inter pore pressure wit moisture change. Extent o

movement depends upon molecular structure and porosity of a material.

Apart from reversible movement certain materials undergo some

irreversible movement due to initial moisture changes after their

manufacture or construction. The incidences of irreversible movement inmaterials are shrinkage of cement and lime based materials on initial drying

i.e. initial shrinkage/plastic shrinkage and expansion of burnt clay bricks

and other clay products on removal from kilns i.e. initial expansion.

b) Thermal movementAll materials more or less expand on heating and contracts on cooling.

When this movement is restraint, internal stresses are set-up in the

component, and may cause cracks due to tensile or shear stress. Thermal

movement is one of the most potent causes of cracking in buildings and callsfor careful consideration. The extent of thermal movement depends upon.

1). Ambient temperature variation


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2).Co-efficient of thermal expansion:- Expansion of cement mortar & concrete

almost twice of the bricks and brickwork. Movement in brickwork in vertica

direction is 50 % more than in horizontal direction.

3. Dimensions of components: -The cracks due to thermal movement is cause

either due to external heat i.e. due to variation in ambient temperature, or due t

internally generated heat i.e. due to heat of hydration in mass concrete durin

construction.

Cracks in the building component due to thermal movement opens and

closes alternatively with charges in the ambient temperature. The concreting

done in summer in more liable for cracking due to drop in temp. in winter

since thermal contraction and drying shrinkage act in unison. Whereas the

concrete job done in the winter in less liable to cracking through it may

require wider expansion joints.

Generally specking, thermal variation in the internal walls and intermediatefloors are not much and thus do not cause cracking. If is mainly the external

walls exposed to direct solar radiation, and the roof, which are subjected to

substantial thermal variation, are more liable to cracking.

c) Elastic DeformationStructural components of a building undergo elastic deformation due to dead

and the super imposed live loads, in accordance with hook law. The amount

of deformation depends upon elastic modulus, meningitides of loading andthe dimension of the component. This elastic deformation under certain

circumstances causes cracking in the building as under: -

1. When walls are unevenly loaded with wide variations in stress in different

parts, excessive shear stress is developed which causes cracking in walls.

2. When a beam or slab of large span undergoes excessive deflection and

there is not much vertical load above the supports (as in the case of roof

slab), ends of beam / slab curl up causing cracks in supporting masonry.

3.When two materials, having widely different elastic properties, are built

side by side, under the effect of load, shear stresses are set up at the interface

of the two materials, resulting in cracks at the junction. Such a situation is

commonly encountered in the constructions of RCC framed structure and

brick masonry panel (external) and partitions (internal) walls.

d) Creep: -In concrete, the extent of creep depends on.


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1. Water & cement content

2. Water cement ratio

3.Temperature and humidity

4. Use of Admixture and pozzalans

5. Age/strength of concrete at the time of loading

6. Size and shape of the component

Creep increases with water and cement content, water cement ratio and

temperature; it decreases with increases in humidity of surroundings and the

age/strength of the material at the time of loading.

Use of admixtures and pozzalans in concrete increases the creep. Creep also

increase with increase in surface to volume ratio of component.

IN brickwork the creep depends upon stress/ strength ratio therefore the

creep in brickwork with weak mortar in generally higher. For example : Forsame quality of brick, creep of brick work in 1:1:6 mortar is 2 to 3 times that

of bricks work in 1:1:3 mortar.

Generally creep in brickwork in approx 20 to 25 % that of concrete. In

brickwork it ceases after 4 months while in concrete it may continue up to a

year or so, and most of creep takes place in 1stmonth thereafter it pace slows

down.

The major affect of creep in concrete is the substantial increase in the

deformation of structural members, which may be to the extent of 2 to 3

times the initial elastic deformation. This deformation sometimes causes

cracks in brick masonry of frame and load bearing structures. When the

deformation due to elastic strain and creep occurs in conjunction with

shortening of an RCC member due to shrinkage, cracking is must more

severe and damaging.

e) Movement due to Chemical reaction

Certain chemical reactions in building materials result in appreciable

increase in volume of materials, due to which internal stresses are setup

which may results in outward thrust and formations of cracks. The materialinvolve in reaction also chemical reactions are.

Sulphate attack

Carbonation in cement based materials

Corrosion of reinforcement in concrete and brickwork

Alkali aggregate reaction


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f) Foundation movement and settlement of soil:

Shear cracks in buildings occurs when there is large differential settlement

of foundation due to one of the following causes.

1. Unequal bearing pressure under different parts of the structure.

2. Bearing pressure being in excess of safe bearing strengths of the soil.

3. Low factor of safety in the design of foundations.

4. Local variations in the nature of supporting soil, which remained

undetected and could not be taken care of the foundations design at the time

of constructions.

5. Foundations resting in active zone on expensive soil.

Leaning PISA TOWER due to settlement

g). Growth of vegetation: -


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Roots of a tree generally spread horizontally on all sides to the extent of

height of the tree above the ground and when the trees are located in the

vicinity of a wall, they can cause cracks in walls due to expensive action of

roots growing under the foundations.

Sometimes plants take root and being to grow in fissures of walls, becauseof seeds contained in bird droppings. If these plants are not removed well in

time, these may in course of time develop and causes serve cracking of wall.

When soil under the foundations of a building happens to be shrinkable clay,

cracking in walls and floors of buildings can occur following ways.

Growing roots of trees cause de-hydration of soil which may shrink and

cause foundation settlement, or

In areas where old trees had been cut of to make way for building

construction roots had be hydrated the soil. ON receiving moisture from

some sources, such as rain etc., the soil swells up and causes an up-ward

thrust on a portion of the building resulting in cracks in the building.

7. COMMON CRACK PATTERNS IN BUILDINGS

The commonly observed crack pattern in building can be group as, cracks in:

a). Walls, b). RCC members,

c). Renderings and plasters, d). Concrete and terrazzo floors, and

e). Roof terrace.

There are some method /preventive measures for repairs of cracks in

specific cases. However, main emphasis should be given on prevention of

cracks, as in many cases there may be no satisfactory method of repairing

the cracks after they have appeared.

a). Cracks in wallsIn masonry structure

i. Cracks at ceiling level in cross wallsii. Cracks at the base of a parapet wall

iii. Horizontal cracks in the topmost story below slab level.iv. Diagonal cracks in cross walls of a multi-story lead bearing structure


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v. Vertical cracks below opening sin line with window jambsvi. Vertical cracks in the top most storey at the corner

vii. Vertical cracks around stair case / balconies openingviii. Vertical cracks in the side walls at the corner of long buildings

ix. Horizontal cracks at lintel / sill level in top storeyx. Diagonal cracks over RCC lintels spanning large opening.

Staff quarters wall cracks

In RCC framed structures

i) Cracking of panel walls ii) Cracking of partition walls

iii) Crack in free standing walls

b. Cracks in RCC members

i) In exposed members

ii) Racks in RCC members due to corrosion of re-inforcement


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c. Cracks in rendering and plastering

i) On masonry background

ii) On concrete background

iii) Cracks around door &window frames

d. Cracks in concrete and terrazzo floors

i).Crazing

ii) Corner cracksiii) Cracking of floor in deep fillings

e. Cracks in roof terrace


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8.COMMON DEFECTS IN BUILDINGS DUE TO

NEGLIGENCE-

These can be classified based on it position and it nature of

construction as under:

a. Improper layoutb. Improper orientation of buildings, far & setbacksc. Casual decision for foundationd. Casual decision of plinth levele. Improper construction of wallf. Construction joint between old/new wall and dissimilar structure.g. Defective RCC work.h.

Improper slope of floors in rooms and bathroomsi. Cracks in the plastering.

j. Breakage of wall & plastering by installation of electrical insulation.k. Improper drainage and sewage line.l. Defects in wooden doors, window and ventilators.m.Defects painting and distempering

a). IMPROPER LAYOUT: Normally layouts are given by lay menwho are not technically sound and efficient. In later stage the following

difficulties may arise due to defective layout of building.

i). Properly squaring of building corner.

ii).Even thickness of courses in building.

iii).Straightness of wall

iv).Levels of the buildings.

v). Gradient of the sewage live.

vi).Gradient of road and connection to the main road

REMADIAL MEASURES

i). Leveling instrument and theodolite should be invariably used for out ofbuildings, surface drainage, sewage disposal or water supply works. No

work should be started be started without installing pegs and bench marks

for centre lines and levels.

ii). The survey instruments should be kept in proper adjustment. Supervisor

should acquire the knowledge and confidence in making permanent


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adjustment. The instruments including the optical parts should be kept clean.

Those should be transported with almost care.

b). IMPROPER ORIENTATION OF BUILDINGS, FAR &

SETBACKS-Orientation of a building is defined as a method of fixing thedirection of the building in such a way that it derives maximum benefit from

sun air and nature. Where possible a house or buildings facing south

direction is regarded to have a best orientation as sun is at low attitude in

winter days. Otherwise a house should be oriented in such a direction in

which wind blows for most of time during the year. Generally in hot regions.

The building facing east direction is preferred to safe guard against westerly

wind.

In railway very casual approach is taken for orientation FAR

& set backs of the building. We are simply constructing our building parallelto otherwise perpendicular railway line without giving proper attention to

the orientation, FAR and set backs.

REMADIAL MEASURESi). Provide proper orientation, far & setbacks based direction of sun, and

wind direction.

c). CASUAL DECISION FOR FOUNDATION

Very casual approach/decision is taken in the matter mentioned below-

i. Arbitrary decision for depth of foundation.ii. Visual decision for level of bottom of foundation.

iii. Not uniform width of foundation.iv. Not properly leveling of foundation.v. Excess excavation of foundation in the in same place.

REMADIAL MEASURES

i. The bottom level of foundation concrete should be governed by thebenchmarks, even for a simple work, such as construction ofcompound wall. Otherwise the longitudinal pro of the wall will

become snaky with undulating terrain.

ii. If square ness of walls in building is not achieved through properinitial setting the blunder will show up when flooring tiles are fixed.


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d). CASUAL DECISION OF PLINTH LEVEL-

We are deciding the plinth level casually without seeing the

following points-

i) Not watching the surrounding to decide the plinth level.ii) Not taking the consideration of approach road at the time, when deciding

the plinth level.

iii) Not watching drainage and sewage disposal in vicinity.

REMADIAL MEASURESi. Plinth level of a building should be carefully decided depending on

site conditions post history of flood level and future level of the

serving roads.

ii. Where plinth masonry is of brick has the super structural and has no

plinth offset, there should be a groove in plastering of exterior wall.The plinth masonry thus demonstrated should receive darker colour to

suppress earth-splash due to rains. This scheme will also add to the

appearance of the building.

iii. If RCC belt or plinth beam is provided at plinth level it should be castat such a distance below floor level, so that any sewer pipe called is

clearly above the belt or beam. The structural designer also should

remember this point.

e. IMPROPER CONSTRUCTION OF WALL -

We are not giving due consideration on the following points.

i. Improper ratio of opening.ii. Plumb ness of the wall.

iii. Improper sequence of material used in masonry work. as in stonemasonry bigger size stones in lower courses and smaller in upper

courses.

iv. Not proper curing of the work.v. Direction of opening

vi. Not providing leveling course/ bed blocks under lintels, slabs.vii. Not staggering of joints at a particular point.

viii. Not proper bedding of stone/ bricks in the same layer.ix. Filling of gaps in between big stones by small stone/brick pieces

without properly filling of motor.


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x. Not properly mixing of mortar.xi. Thick joints

No proper Bonding at wall junction

REMADIAL MEASURES

i. Adequate attention should be paid while positioning the door andwindow frame with respect to the width of gap, de the hinge side and

deciding the direction of opening of the shutters.

ii. In tropical countries too many windows and glazing are not required.However, of there is a tendency to wear the wall by providing too

much of opening. If a wall between are junctions has openings at

window level totaling to more than 50 to 60% of its length,engineering of wall by RCC pillars is necessary. Further due to

unfavorable positioning of openings, scene locations of masonry may

get weakened. In such situations also RCC pillar may have to be

provided on the openings may have to be provided on the openings

may have to be repositioned. Plasters in masonry as adopted in olden

days are not just for luxury or look these have structural function too.


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Every civil engineer should be conversant with the principles of brick

masonry design, as explained in the National Building Code. No

location on the earth is free of the earthquake possibility. Careful

design and construction of masonry may save many lives in future.

iii. 3. RCC bed block should be provided at the bearing of beam carryingheavy load and resting on brick wall, to avoid stress concentration,

even if drawing fails to details the same.

f. CONSTRUCTION JOINT BETWEEN OLD/NEW

WALL AND DISSIMILAR STRUCTURE-i. Casual approach is being taken for joining of masonry of new

work with the old work resulted cracks in between both the work.

ii. If we are constructing the main building along with the compoundwall etc. (i.e. dissimilar work) and taking the work continuously

without providing construction joints the cracks will be developeddue to different loading on the work.

REMADIAL MEASURES

i. Construction must be provided in between dissimilar works right fromthe bottom.

g. IMPROPER BONDING OF DISIMILAR MATERAIL

AND AT JUNCTION OF THE WALLS-

It is because of not proper bonding of masonry in super

structure. Bonding is a process of arranging bricks and mortars to tie them

together in a mass of brick work. It should have a minimum of vertical joints

in any part of the work. It is a weak portion of brick work and should not be

continuous in two successive courses. A wall having continuous vertical

joints can act as independent column. Hence, in such cases, load on wall

shall not be uniformly distributed and there are chances of load settlement. A

more strong and durable brick/stone masonry construction must not havecontinuous vertical joints. It shall distribute load on a wider area and thereby

minimize the tendency to settlement.

At some places some vertical cracks in masonry are seen

near the joints of two angled wall and near the corner of walls. At the time of

construction building masonry work of one wall is taken at a time and

bricks/ stone of each layer is left cantilevered outside the surface of this


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wall. If these cantilever portions are not in proper line and level or not

properly matched with the right angle/ any other angle walls then cracks

may be appeared.

REMADIAL MEASURES

ii. Construction of wall on these location should be done simultaneouslyonboth the location

iii. Proper toothing and jointing should be donej. DEFECTIVE RCC WORK

i. HONECOMBING- If segregation takes places during concretingand mortar is separated from Grit than honeycomb may be seen and

there may be leakage problem at these points. It is very harmful as therusting on reinforcement bars may takes place.

ii. EXPOSITION OF STEEL REINFORCEMENT BARS- If thecover in bottom surface is not properly provided or cover Block has

disturbed during concreting of slab or concreting not properly poured

around the reinforcement bars. Than these bars can be seen from

bottom side . Exposed reinforcement bars may be rusted.

iii. POOR WORKABLITY If water cement ratio is not kept properthan it is harmful to concreting work. If it is less than concreting will

not be workable and concreting will not flow around the


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reinforcement bars. If it is more than segregation takes place than

there may be chances of honeycombing and reinforcement exposition.

iv. IPROPER SLOPE- Generally No slope is provided in RCC slab andif there is any sag at centre or any other place than water is filled in

these pocket resulted seepage in the Slab.

v. IMPROPER SHUTTERING:Shuttering not done with proper careand level props are supported in inclined manner without any lateral

and horizontal bracing. To adjust the height of props bricks are used

.Shuttering joints are not water tight.

Shuttering poles are not vertical position

REMADIAL MEASURES

i. Without using concrete mixer and vibrator no concreting should bedone.

ii. Curing of concrete and mortar works should be ensured asstipulated in code.

iii. All slabs should be cast dense, particularly roof slab. Cover belowreinforcement rods should be ensured at all places, by providing

ample cover blocks in a reliable manner.

h. IMPROPER SLOPE OF FLOORS OF ROOMS ANDBATHROOMS

Sometimes we see that water is stagnant in Bathrooms and tape

water near water closet is flowing in Bath. It is also painful to see that

discharge from Wash Basin is running in open drain in Bath room which is

extremely repulsive and deplorable.

It may be because of the following points.


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i. Hesitating to give the slopes in the main room.ii. Not giving proper slope in bathroom by which water is drained off

regularly.

iii. Joint of the floor tiles is not proper and not in one line.iv. Improper bedding of mortar resulted as breakage of floor tiles corners.v. Proper joints are not giving in case of cement concrete-flooring and

not doing concreting in alternate bays.

REMADIAL MEASUREi). Provide adequate slope in bath and toilet for easy drain out of water.

ii). Slope to be providing in rooms also if is washable.

iii). Proper mortar bedding under the tiles should be ensured.

iv). Do floor concreting with alternate bay not to do as a whole.

i.CRACKS IN THE PLASTERING -

Some times minor cracks are seen in the may be small surface

cracks due to weather effect. It is plastering surface. These may be isolated

at some places .the different type of cracks can be seen in the building.

These cracks may be because of

i. Due to poor work men ship.ii. Due to thermo statically changes in the climate.

iii.

Due to settlement in the building.iv. At the junction of dissimilar structures.v. Not proper bonding on the wall.

vi. Not uniformly of the thickness of the joints.vii. Improper curing of the wall.

viii. Not providing molding and drips.ix. Due to excessive silt in the sand.x. Due to application of plaster before completion of curing time of

masonry work.

xi. Not proper mixing of mortar.REMADIAL MEASURESi). Reference marks to given before starting plastering.

ii). Background surface to be wetted properly in advance.


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iii). Not to use Fine sands having more silt. l. BREAKAGE OF WALL

& PLASTERING BY INSTALLATION OF ELECTRICAL

INSULATION.

iv). Uniform Mortar mixing with adequate water and uniform colour.v). Ensure Curing for 14 days..

vi). Protect open surface direct from sun light.

Sometimes electrical department damage the Plastering and rectifies the

same by applying Cement mortar by hand without using a trowel and

finishing tools. Such Shabby works looks very odd.

As a general practice, when the civil works are completed, the

electrical & communication staff starts their works and damage the civil

works and finished the work by unskilled people. Which looks very dirty?

REMEDIAL MEASURES

i. For Electrical installations should be got prepared by Electricalbranch. Concealed wiring should be planned. Casing and capping may

be the next option

ii. Civil &electrical Engineers should jointly understand the locationwhere electric supply line enters in the building

k. IMPROPER DRAINAGE AND SEWAGE LINE

Generally we show the chocking of Drainage and sewage

line. It may be because of not consideration of following points

i. Not consideration of self cleaning velocityii. Not watching of sewage disposal points before starting of work.

iii. Not providing the required slope in sewage lineiv.

REMADIAL MEASURES

i. In the case of Indian water closes only orissa type pan should be usedwhich has straight boundaries and .. it is a good practice is lower

the where the grill is loaded by a


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ii. Slope of floating in bath and toilets is important. In the case of.. thereshould not be any open. discharge from the parts. The pan should

have any and it should join the

iii. Sun shade should not be allowed to collect water, by providing spoutof large diameter at appropriate levels.

iv. Any hole or patchwork done subsequently for water supply ,sewerageor electrical work should be properly finished and cured, so that these

location dont form source for ingress of water.

v. Sunken slabs should invariably provide for bathrooms and toilets inframed structures, the beam of outer wall of toilets though which the

sewer pipes emerge must be case at lower or higher level so that there

is no need to make holes in the beam to pass the pipes. The structural

drawings should show these details clearly.

m. DEFECTS IN WOODEN DOORS, WINDOW AND

VETILATORS

Freshly cut unseasoned wood are used in buildings for wooden door

and window works. Wood which are not fit for woodwork, joinery also used

in construction. At a time wood having moisture content up to 25% are used,

which will leads to warping, bending and cracking and finally it will end up

with door and windows not closing properly and gap will be there all-round

between frames and shutters. Some time sap wood also used for making

door and windows it is soft work portion and it will not withstand for long

time ,using soft wood to be avoided.

Remedial Measures

i. Use seasoned hard country wood or teakwood with moisture contentless than 12%.

ii. Sapwood, cracked ring wood and soft wood not to be used.

iii. Joints in wooden members should be snugly fitted, using the righttype of joints.

iv. It is a good practice to nail wooden beadings around door and windowframes, so as to cover the shrinkage cracks between wood and wall.

Ready- made teak wood beadings of various designs are available in

the market.


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v. Provide sufficient hold fast in each door frames, to hold in firmposition.

n. DEFECTS PAINTING AND DISTEMPERING

SURFACE PREPARATION FAULTS:-Paint failures can resultfrom many causes. Here, well look at some of the most common caused byfaults in surface preparation.

Alligatoring: Alligatoring refers to a coating pattern that looks like the hide

of an alligator. It is caused by uneven expansion and contraction of the

undercoat. Alligatoring can have several causes: applying an enamel over an

oil primer; painting over bituminous paint, asphalt, pitch, or shellac; andpainting over grease or wax.

Alligatoring .

Peeling: Peeling results from inadequate bonding of the topcoat with the

undercoat or the underlying surface. It is nearly always caused by inadequate

surface preparation. A topcoat peels when applied to a wet, dirty, oily or

waxy, or glossy surface. All glossy surfaces must be sanded before painting.

Also, the use of incompatible paints can cause the loss of adhesion. The


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stresses in the hardening film can then cause the two coatings to separate andthe topcoat to flake and peel.

Peeling.

Blistering: Blistering is caused by the development of gas or liquid pressure

under the paint. The root cause of most blistering, other than that caused by

caused by excessive heat is inadequate ventilation plus some structural

defect allowing moisture to accumulate under the paint. A prime source of

this problem, therefore, is the use of essentially porous major construction

materials that allow moisture to pass through. Insufficient drying time

between coats is another prime reason for blistering.


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Blistering.

Inadequate Gloss: Sometimes a glossy paint fails to attain the normal

amount of gloss. This may be caused by inadequate surface preparation,

application over an undercoat that is not thoroughly dry, or application incold or damp weather.

IMPROPER APPLICATION

It takes a lot of practice, but able to eliminate the two most common typesof application defects: crawling and wrinkling.

Crawling:Crawling is the failure of a new coat of paint to wet and form a

continuous film over the preceding coat. This often happens when latex

paint is applied over high-gloss enamel or when paints are applied on

concrete or masonry treated with a silicone water repellent.


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Not all painting defects are caused by the individual doing the job. It

sometimes happens that the coating itself is at fault. Chalking, checking, and

cracking are the most common types of product defects.

Chalking:Chalking is the result of paint weathering at the surface of thecoating. The vehicle is broken down by sunlight and other destructive forces,

leaving behind loose, powdery pigment that can easily be rubbed off with

the finger. Chalking takes place rapidly with soft paints, such as those basedon linseed oil. Chalking is most rapid in areas exposed to sunshine.

Checking and Cracking: Checking and cracking are breaks in a coatingformed as the paint becomes hard and brittle. Temperature changes cause the

substrate and overlying paint to expand and contract. As the paint becomes

hard, it gradually loses its ability to expand without breaking. Checking

consists of tiny breaks in only the upper coat or coats of the paint filmwithout penetrating to the substrate. Cracking is larger with longer breaks

extending through to the substrate. Cracking generally takes place to a

greater extent on wood, due to its grain, than on other substrates. The stress

in the coating is greatest across the grain, causing cracks to form parallel to

the grain of the wood. Checking and cracking are aggravated by excessively

thick coatings that have reduced elasticity. Temperature variations,

humidity, and rainfall are also concerns for checking or cracking.

Severe Checking Severe Cracking.

o. OTHER PRECAUTIONS

i. For new building drawing should be prepared to details the scheme ofroot dia and the positioning of down pipes


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ii. Access to open terrace should be made available should be madeavailable in all buildings by providing reliable service ladders, in case

extended staircases ac not exist. This is to enable engineering staff to

clean and to attend to bad spots in weathering course. This will be a

positive step to avoid leakage problems.

iii. It is a bad practice to leave the droppings of cement mortar on thefloor, sun and open terrace and allow them to set permanently. This

leaves a poor impression of the engineers in the minds of the building

users.

9.CONCLUSIONS &SUGGISIONS:

From the above it has been seen that defects are non-structural cracks

and majority of common defects are due to negligence of Engineers. Also

proper supervision available in most of the woks spot.

In Railway supervision of building construction is left to field staff

i.e SSE/SE/JE (Works) since higher officials are busy in their office and

track work and building works are totally neglected. The field supervisors of

open line are also busy with their regular Building, bridge and road

maintenance work, routine inspections, and staff matters. Some of the

supervisors are also not having adequate technical knowledge about buildingworks.

The present system of supervision will not help to improve the defect

free construction and also it will reduce the maintenance burden and cost.

Some specialized training/courses in building construction, modern

materials and in foundation Engineering may be arranged for from field

level supervisor to Divisional Engineer level. The higher officials are afraid

to exercising the power of deciding the type and depth foundation based onthe site condition.


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THANKS

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