PunJab Training Resource

8/7/2019 PunJab Training Resource

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Earthquake Preparations Preventive & Curative-

A note By P Eng Suraj SinghFrom: Hsrai

To: suraj

Posted: 28 Oct 2009 17:40

Subject: Request for resource person: EQ Risk Management

Respected Sir,We are conducting a course entitled "Capacity Building of Engineers in Earthquake Risk Management" during 2nd week of Dec 2009 i.e 7-12 Dec. I request you to spare one or two day, and be part of this course asresource person [even you may suggest to add or remove something]. The contents of course may be accessed by visiting:http://gndec.ac.in/civil/tp/, then click on "Contents"The course is meant for working professional of Govt. Department. Hoping to see you at GNDEC, Ludhiana. With kind regards, --Dr. M.S. [email protected] No. 0161-2490339, 2502700 Fax No. 0161-2502240 Guru N anak Dev Engineering College Gill Park Ludhiana 141006 Punjab(India)Head of the Department Civil Engineering Department Guru Nanak Dev Engineering College Ludhiana (Punjab)

Pin: 141006 India Phone: 91 161 2490 339 Ext 208 Email:[email protected]. H.S.Rai Prof. and HeadCivil Engineering Departmenthttp://gndec.ac.in/civil/Guru Nanak Dev Engg. Collegehttp://gndec.ac.in/ Ludhiana (Pb) India Mobile 098552 25007

San 2010 ki Aap Sabhi Ko Shub Kamnai (Happy Year 2010 To All)

Course schedule: Dec 28/12/2009 to 2/1/2010 /

This Talk On 01/01/2010 to 02/01/2010

EQ Risk Management Note

Scope Of This Session

Earthquake Preparations Preventive & Curative

Go To Seismology & Rock Mechanics.

Go To Soil Mechanics and Earthquake Resistant Design

Go To Soil-Structure Interaction and Foundation Design

Go To Site Planning, Building Forms and Architectural Design Concept forEarthquake Resistance.

Go To Structural Systems For Earthquake Resistance.

Go To Structural Analysis: Gravity and Lateral Loading.

Go To Structural Design and Ductile Detailing.

Go To Strength & Retrofitting of Structures & Vulnerability Assessment.

Go To Seismic Risk Management in Action.

Go To Effect on Natural and Built Environment

Go To Reference Example & QA

Presentation ByProfessional Engineer Suraj Singh

1 of 35 54848414.doc [email protected]
http://gndec.ac.in/civil/tp/http://gndec.ac.in/civil/tp/http://gndec.ac.in/civil/tp/mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://gndec.ac.in/civil/http://gndec.ac.in/civil/http://gndec.ac.in/civil/http://gndec.ac.in/http://gndec.ac.in/http://gndec.ac.in/mailto:[email protected]:[email protected]:[email protected]://gndec.ac.in/civil/http://gndec.ac.in/mailto:[email protected]://gndec.ac.in/civil/tp/


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A note By P Eng Suraj Singh25 Years + Experience (18 Years Overseas) RCC Buildings & Onshore Oil

Thanks to Dr. H.S.Rai Prof. and HeadCivil Engineering Department extendingme an opportunity for this presentation

Back Earthquake Preparations Preventive & Curative:This presentation is meant for the civil field engineers & high ups to apprise themselvesabout the earthquake involvement factors that make an impact on building designs. No

engineering formulas are included herein due to the fact that all qualified engineers have

learnt that during engineering training. This document is submitted as an objectiveprojectile to those aspiring for practical potential backup know how & meant only for

refreshing respective reader about the subject. Easy text has been used while composing

the descriptive information. It is hoped that readers would find the explanationsinteresting for updating professional awareness. It is generally meant for the middle level

government, corporate sector engineers & other engineering buds. No new knowledge

has been added but rather, a collection of various already known information, has beenmade for the assistance of reader to serve as a reference, whenever required. It is advisedthat civil/structural engineers have been interacting regularly on www.sefindia.org

whereon, all you good engineer may raise questions for experts feed back & suggestions.

You may also advise the budding engineers. Many of you are experts in the governmentservices operation thereby, by virtue of which specialization, you may help the nation.

Please refer to various slides & other documents from various sources

included to support this note.

Back Seismology & Rock Mechanics:Prior to entering to deliberate the subject, it is advisable to refresh about the Earths crust

from Applied Science of Geology view point. Applied Geology is a branch of Earthsscience that is a must to be understood by any Civil Engineer without which, a civil

engineer would definitely feel missing a lot about the structural foundations.

Lithosphere Indicative Model

Lithosphere Model On Cad

Preliminary explanation regarding Lithosphere:

Earth- What is meaning of Earth? Is it the globe solid surface? What else consists ofEarth? What relevance does it have on the system of this planet towards environment up

to space?

Earth= Lithosphere + Aerosphere = Solid globe + Air envelope surrounding

Lithosphere

Lithosphere = Solid portion of Globe = About 12000 Km generallyLithosphere = Core + Mantle + Crust: where crust is uppermost, Mantle is in the

intermediate portion while Crust is within top 35 Km.

http://www.sefindia.org/http://opt/scribd/conversion/tmp/LithosphereModel.xlshttp://opt/scribd/conversion/tmp/Globe.dwgmailto:[email protected]://www.sefindia.org/http://opt/scribd/conversion/tmp/LithosphereModel.xlshttp://opt/scribd/conversion/tmp/Globe.dwgmailto:[email protected]


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A note By P Eng Suraj Singh

1. Crust represents such as skin of an apple containing all seas & oceans.

2. Mantle goes down to about 2500 Km of Lithosphere interior with increasing

temperature & densification of material in.

3. Core goes further down to the centre of Lithosphere where materials are found in

liquid state but with higher densities & rising temperatures.

4. Crust generates all earth quakes actions in the form of rocking of earth crust due

to the stored strain energy within, that is released due to imbalance & the release

continues until re equilibrium is established.

5. A parallel portion to the Lithosphere up to say 18 to 20 km from sea or surface

constitutes aerosphere within which volume, various gases, photons, sun rays

involving huge chemical reactions work that are responsible for changing

regularly occurring on Lithosphere.

6. Generally speaking, the seas constitutes up to 4 Km of sea level while oceans godown up to 10 Km. The sea or oceanic floors are generally basaltic in nature

having stronger rocks.

7. Lithosphere Crust portion, creates by eruption of magma/lava, by wind erosion,

by environment adverse effects, by variation of temperatures, by works of various

other agencies effects imposition, do form various types of topping of crust such

as rocks classified as Volcanic, Sedimentary & Metamorphic that are responsibleto force all engineers to fit their designs according to the properties of these beds.

Similarly, wind erosion responds to the formation of sands beds or alluvial planes.

8. Due to the continuous movements by the release of volcanic material as said by

magma erupting & in some places, entering in to the crust again by convection

after having cooled immensely, the cycle works to impose various changes on thecrust & in particular, on the limits within which the foundations are to be placed.

Rock movement by the name of Plutonic Plates involved motion keep on working

& their movement towards each other, make extension of continents while theirbreaking at certain points forms new continents.

Earthquakes are defined as, Ground shaking and radiated seismic energy caused mostly

by sudden slip on a fault, volcanic or any sudden stress change in the earth.

PresentationEQ.ppt

Back Soil Mechanics and Earthquake Resistant Design:

1. Should we call Applied Geology as the title subject, soil mechanics is the chapter

like subordinate subject. Earthquake Resistant Design is a specialist subject then.

http://opt/scribd/conversion/tmp/scratch17710/PresentationEQ.pptmailto:[email protected]://opt/scribd/conversion/tmp/scratch17710/PresentationEQ.pptmailto:[email protected]


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A note By P Eng Suraj Singh2. Soil Mechanics = Soil Engineering +Soil Static + Soil Dynamics +Soil Testing,

Exploration & Reporting + Soil Tomography + Soil Development + Soil

Foundation Interactions

3. All naturally formed materials whatever is available in any form, in portion

utilizable for foundations inclusion of any structure, is or can be called soil &includes all rocks, sands, clays, silts, gravels, pebbles & soil water etc.

4. Soil Mechanics operations are solely responsible to tell engineer what to do todecide about any foundation? When all soil investigation reports are available in

elaborate details, no need arises to make any approximate assumptions keeping in

view the generality of the proposed foundations areas. Based on these soilsperformance in the long past resembling to the available rocking data, with

assessed EQ intensity, the zoning of the areas are carried out. That provision of

designating any area any where, is termed as Seismic Zoning.

5. An engineer who understands the clear concept of available reports from thematerials testing laboratory, would be in a definitely certain position to make a

good decision on the design based on the soil engineers recommendations withadditions of his own interpretation of the reports parameters. Earthquake resistant

effects shall be rightly provided within the proposed foundations in such a

situation of engineers interpretations of the reports. It is also true that detailedstudies are never made in the educational training programmes anywhere. Even,

the master degrees do not provide detailed understanding about EQ, the most

significant subject from design engineering viewpoints.

Back Soil-Structure Interaction and Foundation Design:

1. This topic is in continuation to the foregoing explanation as the foundation is tobe placed on soil while the two parts of structural & soil component must worktogether integrally for the successful performance of any sub structural system.

2. Soil may contain any compact or spatial structure or cohesive or frictional

structural grains depending on soil nature. It may also be constructed of platelets.Even rocks may be adversely affected by the weak planes faults or bends or

cracks or fissures or cavities. Rock may be weathered. Soil could be clay or silt or

sandy or peat or other. All soils work with the foundations in one form or otherbut are supposed to work as a team for a successful safe foundation.

3. Water being dangerous by its presence in the soil or rock mass either in moisture

form or laminar or turbulent flow form. Since, soil contains various chlorides or

sulphides or various types of carbonates in either loose or in dissolved form &these compositions keep on altering for years & decades, may affect the soil

performance badly. Water keeps moving within voids & with that, provides all

these chemicals to soil that changes the soil chemical properties affecting itsperformance or resisting power. Water is better to be kept off the soil mass by

providing various means or methods of constructions.

mailto:[email protected]:[email protected]


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A note By P Eng Suraj Singh4. Permeability is a property that allows water to flow within soil mass of

interconnecting voids soils. Sand, gravels, pebbles etc constitute such soils. Such

soils are dominated by angle of internal friction.5. Porosity is the property that allows water to remain stored for certain duration

within soil mass imposing soil swelling pressure from within voids. Clay & Silt

are such soils. Such soils are badly affected by capillary actions. Foundations aredesigned based on all these considerations by applying the interactions between

the available soil strata & the proposed foundation elements. Such soils are

dominated by cohesion.

Ref CRC Press: Earthquakes are naturally occurring broad-bandedvibratory ground motions, caused by a number of phenomenaincluding tectonic ground motions, volcanism, landslides, rockbursts and human made explosions. Of these various causes,tectonic-related earthquakes are the largest and mostimportant. These are caused by the fracture and sliding of rock

along faults within the Earths crust. A fault is a zone of theearths crust within which the two sides have movedfaultsmay be hundreds of miles long, from 1 to over 100 miles deep and notreadily apparent on the ground surface. Earthquakes initiate a numberof phenomena or agents termed seismic hazards, which can causesignificant damage to the built environmentthese include faultrupture, vibratory ground motion (i.e. shaking), inundation (e.g.tsunami, seiche, dam failure), various kinds of permanent groundfailure (e.g. liquefaction), fire or hazardous materials release. For agiven earthquake, any particular hazard can dominate and historically,each has caused major damage and great loss of life in specific

earthquakes. The expected damage given a specified value of a hazardparameter is termed vulnerability and the product of the hazard andthe vulnerability (i.e. the expected damage) is termed the seismicrisk.

Ref CRC Press LLC Causes of Earthquakes and FaultingIn a global sense, tectonic earthquakes result from motion between anumber of large plates comprising the earths crust or lithosphere(about 15 in total). These plates are driven by the convective motionof the material in the earths mantle, which in turn is driven by heatgenerated at the earths core. Relative plate motion at the fault

interface is constrained by friction and /or asperities (areas ofinterlocking due to protrusions in the fault surfaces). However, strainenergy accumulates in the plates, eventually overcomes anyresistance and causes slip between the two sides of the fault. Thissudden slip, termed elastic rebound by Reid based on his studies ofregional deformation following the 1906 San Francisco earthquake,releases large amounts of energy, which constitutes theearthquake. The location of initial radiation of seismic waves (i.e. the



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A note By P Eng Suraj Singhfirst location of dynamic rupture) is termed the hypocenter, while theprojection on the surface of the earth directly above the hypocenter istermed the epicenter. Other terminology includes near-field (withinone source dimension of the epicenter, where source dimension refersto the length or width of faulting, whichever is less), far-field(beyond

near-field), and meizoseismal (the area of strong shaking anddamage). Energy is radiated over a broad spectrum of frequenciesthrough the earth, in body waves and surface waves. Body wavesare of two types: P waves (transmitting energy via push-pull motion),and slower S waves (transmitting energy via shear action at rightangles to the direction of motion). Surface waves are also of two types:horizontally oscillating Love waves (analogous to S body waves) andvertically oscillating Rayleigh waves.

While the accumulation of strain energy within the plate can causemotion (and consequent release of energy) at faults at any location,

earthquakes occur with greatest frequency at the boundaries of thetectonic plates. The boundary of the Pacific plate is the source ofnearly half of the worlds great earthquakes. Stretching 40,000km around the circumference of the Pacific Ocean, it includesJapan, the west coast of North America and other highlypopulated areas and is aptly termed the Ring of Fire. Theinteriors of plates such as ocean basins and continental shields, areareas of low seismicity but are not inactive the largest earthquakesknown to have occurred in North America for example, occurred in theNew Madrid area far from a plate boundary. Tectonic plates movevery slowly and irregularly with occasional earthquakes. Forces

may build up for decades or centuries at plate interfaces untila large movement occurs all at once. These sudden, violentmotions produce the shaking that is felt as an earthquake. Theshaking can cause direct damage to buildings, roads, bridges,and other human-made structures as well as triggering fires,landslides, tidal waves (tsunamis), and other damagingphenomena.

Faults are the physical expression of the boundaries between adjacenttectonic plates and thus may be hundreds of miles long. In addition,there may be thousands of shorter faults parallel to or branching out

from a main fault zone. Generally, the longer a fault the larger theearthquake it can generate. Beyond the main tectonic plates, there aremany smaller sub-plates (platelets) and simple blocks of crust thatoccasionally move and shift due to the jostling of their neighborsand/or the major plates. The existence of these many sub-platesmeans that smaller but still damaging earthquakes are possible almostanywhere, although often with less likelihood.



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Generally, earthquakes will be concentrated in the vicinity of faults.Faults that are moving more rapidly than others will tend to havehigher rates of seismicity and larger faults are more likely than othersto produce a large event. Many faults are identified on regional

geological maps, and useful information on fault location anddisplacement history is available from local and national geologicalsurveys in areas of high seismicity. Considering this information, areasof an expected large earthquake in the near future (usually measuredin years or decades) can be and have been identified. However,earthquakes continue to occur on unknown or inactive faults. Animportant development has been the growing recognition of blindthrust faults, which emerged as a result of several earthquakes in the1980s, none of which were accompanied by surface faulting. Blindthrust are faults at depth occurring under anticlinal foldssince they have only subtle surface expression, their

seismogenic potential can be evaluated by indirect meansonly. Blind thrust faults are particularly worrisome becausethey are hidden, are associated with folded topography ingeneral including areas of lower and infrequent seismicity andtherefore, result in a situation where the potential for anearthquake exists in any area of anticlinal geology even if,there are few or no earthquakes in the historic record. Recentmajor earthquakes of this type have included the 1980Mw 7.3 El-Asnam (Algeria), 1988 Mw 6.8 Spitak (Armenia), and 1994 Mw 6.7Northridge (California) events. Probabilistic methods can be usefullyemployed to quantify the likelihood of an earthquakes occurrence, and

typically form the basis for determining the design basis earthquake.

Tsunami:

Tsunami is a Japanese word meaning The Harbor Wave.

Shallow water waves with destructive potentials that propagate with greater speeds

transferring tectonic energy towards land from beds across oceans increasing in height asthey approach land.

Causes of Tsunamis:

Tsunamis are usually caused by underwater earthquakes often, occuring offshore at

subduction zones (a tectonic plate that carries an ocean gradually slips under a

continental plate). A receding sea usually precedes a tsunami wave. In most cases there isalso drawdown of sea level preceding crest of the tsunami waves.

Landslides can also cause tsunamis by displacing large volumes of water.

If Volcano collapses and slides into the ocean it may also create a very large tsunamiwave.

They are caused by earthquakes or landslides.



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A note By P Eng Suraj SinghTsunamis can be generated when the seafloor abruptly deforms vertically displacing

large volume of water which under the influence of gravity forms waves around it in

order to reach equilibrium .Displaced water mass.

Tectonic earthquakes can cause tsunamis when a tectonic place subsides or rises. Along

plate faults, is where vertical movements of plates take place. Subduction zones areusually sources of large tsunamis. During subduction earthquake, offshore ocean bottom

lifts up the land along the coast lowers down.

However, an earthquake generating process is notunderstood well enough to reliably predict the times,sizes, and locations of earthquakes with precision. Ingeneral, therefore, communities must be prepared forfacing an earthquake to occur at any time. No nationis perfect in EQ Risk Management. Only prevention &

post EQ disaster management can be ascertained byone & all responsible citizens.

Back Site Planning, Building Forms and Architectural

Design Concept for Earthquake Resistance:

1. Prior to starting planning for any building site, it is a requirement particularly for

projects going to consume high quantity of concrete & other reinforcement, to

carry out a reasonable level of soil investigation & the report should be madeavailable to the designer immediately for studies & a good understanding of

recorded parameters. Prior investigation of soil may also indicate the nonsuitability of the proposed site or it would be uneconomical from various aspects

or constructability / build ability issue may cause a problem for a smooth passageof construction.

2. Practice had been that an architect used to conceive any building & produces itsenvelope details to ideals thought of. This applied to buildings constructed of

stone or brick masonry. Should one refer to old buildings for example Taj Mahal

or Red fort or even old houses /havelees, one would find walls too thick. Iremember one of my professor in 1974 instructed that brick single wall of 225

mm could take the building safely up to 3 storey with 3 to 4 m span size room.

Actually, in those days there, was no consideration of Earthquake Resistance

technologies that can help a lot buildings construction in general.

3. After conception of any building at schematic stage, next step should be to fit in

the dream on to the proposed available plot. The complete setting out of the mainas well as ancillary buildings follows & the plan is given final architectural touch

including an attractive perspective or an isometric view. These plans are given to

the engineer to insert in the structural mechanism or skeleton in to it to satisfy the



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A note By P Eng Suraj Singhdemanded requirements by the architect. Various instances have been witnessed

where the architect defines the dimensions of the column sections with locations.

These conditional qualifications on the given drawings generally, prohibitengineer to work independently for making design decisions about the framing of

the building.

4. Meetings are held to explain to the architect about the forces compatibility

problems caused by the defined locations & members sizes. In case, architect is

rigid on assumed locations, engineer may not help the design to amend but tocontinue designing on the given locations. Best practice would have been had the

architect given a free hand to designer to locate the members & then discuss with

the architect about the adoptability for a better structural formation. Duringmechanizing process of the structure, an engineer can conceive & anticipate

where to & in which locations of members, critical forces would generate &

would help members to be correctly located to respond to earthquake language.

5. Analysis of the superstructures can be easily carried out to meet givenrequirements in accordance with various recognized structural systems for

multistory & high rise buildings. For low rise buildings structures, a lot dependson the concept of design engineer to chart out decisions for the projections of

possible foundations. Since variations do occur for the spans fixing, that would

certainly make the structures different in the substructure as well as superstructureformation mechanism.

6. Facets demanded makes a difference on the structural framings. Architects

generally intend to hide the structural members while, these also can add to thebuilding elevations. Any low rise building can be analysed by 2 D or 3 D systems.

I have used for many analysis the non practiced Kanis Rotation Contributionmethod that provided reliable forces to be adopted for designing & detailing.Earthquake resistance solution parameters & formula to be used, which have been

coded as well as given in the available literature. But as a thumb rule, a 25 %

building mass can be used as horizontal seismic shear around the whole building.

7. It is also kept in view that wind loads & seismic forces do not act together. Only

one should be considered one time. It is a fact that horizontal forces would impactthe structure to be deflected or swayed away diagonally introducing torsion into

the building as well as transferring moments to the foundations. All these

developed forces need considerations of adjustments within designs.

8. Main point herein is to know how to develop a structure that would resist the

seismic actions resulting vibrations being imposed on the building to be

dampened gradually within seconds of applications of the forces. This methodneeds to be considered at all levels of the structures. Seismic forces act at the

foundations laterally & continue to transfer to the upper levels. In fact, we can

consider a building as a machine for all practical purposes. Reliable stability canbe provided to the soil foundation system.



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9. Building should be as light as possible. Light building means low mass value.

10. Foundations should be spread in such a way that maximum area of soil contact isfeasible. Maximum contact area means low upward reaction.

11. Foundation structure should not localize the upward reactions but spreaden as

uniform distributed reaction load.12. Foundation should rest on a soil that would provide the required safe bearing

capacity as well as have good shear resistance with minimum predicted

settlement. Minimum settlement & reaction UDL economise construction cost.13. Need not mention that unequal settlement should be avoided.

14. Let us take example of a wooden stool that is constructed sometimes, byproviding either vertical post or by inclined posts duly tied at the bottom or top of

the posts. This stool is stirred horizontally but it remains stable after vibrations.

Similar concept can be applied to any building just to understand the basics.

15. Generally, Buildings are provided with cantilever footings/spreadfootings/independent foundations. Well, these foundations work acceptably fine

to the requirement of direct load & also, part of bending moments but, thecantilever is not supposed to be economical as it does not work safely when

imposed upon by EQ vibratory forces.

16. One way to come out of this problem is to add connecting beams to foundations

level or at the plinth level. If connected at the foundation level, these may share

foundation loads jointly with the foundation pads. At plinth level, these would add

to the stability of the lower storey columns. These have been successful fordecades.

17. Seismic forces while acting horizontally need concrete members to digest/absorbor dampen the forces. In case, all these foundations & connecting or plinth beams

are replaced by the standalone beam frames in both directions as a mat or to work

in stool fashion, a considerable dimension diaphragm shall be available for theseismic forces to be resisted with. In this situation, all the beams in both directions

shall work as a frame while depth of the frame being considerable say 900 mm to

1200 mm or even 1500 mm with 300 to 500 mm width. This can well apply toordinary low rise buildings say up to 4 to 5 stories high.

18. Advantage would be that absenting cantilever actions would result in less bending

moments. The imposed lateral forces shall be comfortably resisted. All theseframe members in both directions shall act as virtual columns during earthquake

allowing only small fraction of forces to the superstructure.

19. I have used this method for many designs successfully. Since, foundations are in

beam form, skin reinforcement too shall be provided. Stirrups shall run all

ways/grids of the framings adding to the shear resistance, punching resistance &providing adequate development length to column reinforcing bars. The portion



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A note By P Eng Suraj Singheven if overstressed in inelastic or non linear range. Size control on section can

also be established in a good way.

24. Foundations & structures should talk same language during setting out the floor

plans to keep the centre of gravity of the loads & plans nearly same. Rigidity cg

should pass in line with mass cg. An attempt should be made to avoid undesiredcantilevers for aesthetic purpose & if so necessary to be included with, should be

adequately designed keeping restrictions on the span. Torsion provision is a must

on this member supporting beams. Cantilever requires 5 times strengthening thannon cantilever members to resist EQ forces. It is also a good detailing practice to

avoid unnecessary overlaps if it is feasible to continue the rebars to the extent of

standard lengths. Higher dia bars should be mechanically connected for betterworking using high strength couplers.

25. High rise or multistory structures are generally designed on pile foundations but it

is also not right to say that piles are indispensable to some extent if good

responsive soil is available. We should remember that piles too are subject tohorizontal force during seismic occurrence & there is a possibility for socketed or

friction pile to deflect during EQ attack. In case, rock or good soil is availablewithin foundation scope, it is better to accommodate foundations within that

portion avoiding piles. Soil can be improved by many methods applications to

erect on heavy foundations. Water has to be kept out of coming in contact withfoundations & soil. On various floors of high rise structures, various dampers can

be provided that would dissipate passive energies generated from the seismic

effects.

Ref CRC PressMetallic Yield DampersOne of the effective mechanisms available for the dissipation of energyinput to a structure from an earthquake, is through inelasticdeformation of metals. The idea of utilizing added metallic energydissipators within a structure to absorb a large portion of the seismicenergy began with the conceptual and experimental work of Kelly et al.

Friction DampersFriction dampers utilize the mechanism of solid friction that developsbetween two solid bodies sliding relative to one another to provide thedesired energy dissipation. Several types of friction dampers havebeen developed for the purpose of improving seismic response ofstructures.

Viscous Fluid DampersDamping devices based on the operating principle of high-velocity fluidflow through orifices have found numerous applications in shock andvibration isolation of aerospace and defense systems. In recent years,research and development of viscous fluid (VF) dampers for seismic



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A note By P Eng Suraj Singhapplications to civil engineering structures have been performed toaccomplish three major objectives. The first was, to demonstrate byanalysis and experiment that viscous fluid dampers can improveseismic capacity of a structure by reducing damage and displacementswithout increasing stresses. The second was, to develop mathematical

models for these devices and demonstrate how these models could beincorporated into existing structural engineering software codes.Finally, the third was, to evaluate reliability and environmental stabilityof the dampers for structural engineering applications.

As a result, VF dampers have in recent years been incorporated intocivil engineering structures. In several applications, they were used incombination with seismic isolation systems. For example, VF damperswere incorporated into base isolation systems for five buildings of thenew San Bernardino County Medical Center, located close to two majorfault lines in 1995. The five buildings required a total of 233 dampers

each having an output force of 320,000 lb and generating an energydissipation c

Tuned Mass Dampers TMDThe modern concept of tuned mass dampers (TMDs) for structuralapplications has its roots in dynamic vibration absorbers, studied asearly as 1909 by Frahm. Under a simple harmonic load, one can showthat the main mass can be kept completely stationary when thenatural frequency of the attached absorber is chosen or tuned to bethe excitation frequency.

Tuned Liquid Dampers TLDThe basic principles involved in applying a tuned liquid damper (TLD)to reduce the dynamic response of structures, are quite similar tothose discussed above for the TMD. In effect, a secondary mass in theform of a body of liquid is introduced into the structural system andtuned to act as a dynamic vibration absorber. However, in case ofTLDs, the response of the secondary system is highly nonlinear dueeither to liquid sloshing or the presence of orifices. TLDs have alsobeen used for suppressing wind-induced vibrations of tall structures. Incomparison with TMDs, the advantages associated with TLDs includelow initial cost, virtually free maintenance and ease of frequency

tuning. It appears that TLD applications have been installed primarilyin Japan. Examples of TLD-controlled structures include the NagasakiAirport Tower, installed in 1987, the Yokohama Marine Tower, alsoinstalled in 1987, the Shin-Yokohama Prince Hotel, installed in 1992,and the Tokyo International Airport Tower, installed in 1993. The TLDinstalled in the 77.6-m Tokyo Airport Tower, for example, consists ofabout 1400 vessels containing water, floating particles and a small



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A note By P Eng Suraj Singhamount of preservatives. The vessels shallow circular cylinders 0.6 min diameter and 0.125 m in height, are stacked in six layers on steel-framed shelves. The total mass of the TLD is approximately 3.5% ofthe first-mode generalized mass of the tower and its sloshingfrequency is optimized at 0.743 Hz. Floating hollow cylindrical

polyethylene particles were added in order to optimize energydissipation through an increase in surface area together with collisionsbetween particles. The performance of the TLD has been observedduring several storm episodes. In one such episode, with a maximuminstantaneous wind speed of 25 m/s, the observed results show thatthe TLD reduced the acceleration response in the cross-wind directionto about 60% of its value without the TLD.

Active ControlAs mentioned, the development of active or hybrid control systems hasreached the stage of full-scale applications to actual structures. Since

1989, more than 20 active or hybrid systems have been installed inbuilding structures in Japan, the only country in which theseapplications have been installed. In addition, 14 bridge towers haveemployed active systems during erection.

Back Structural Systems For Earthquake Resistance:CRC Press LLC Rigid FramesA rigid frame derives its lateral stiffnessmainly from the bendingrigidity of frame members interconnected by rigid joints. The jointsare designed in such a manner that they have adequate strength,stiffness and negligible deformation. The deformation must be small

enough to have any significant influence on distribution of internalforces and moments in the structure or on overall frame deformation.

A rigid unbraced frame should be capable of resisting lateral loadswithout relying on an additional bracing system for stability. The frameby itself, has to resist all the design forces including gravity as well aslateral forces. At the same time, it should have adequate lateralstiffness against sidesway when it is subjected to horizontal wind orearthquake loads. Even though, the detailing of the rigid connectionsresults in a less economic structure, rigid unbraced frame systemshave the following benefits:

1. Rigid connections are more ductile and therefore, the structureperforms better in load reversal situations or in earthquakes.2. From the architectural and functional points of view, it can beadvantageous not to have any triangulated bracing systems or solidwall systems in the building



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A note By P Eng Suraj SinghBraced Frames vs. Unbraced FramesThe main function of a bracing system is to resist lateral forces.Building frame systems can be separated into vertical load-resistanceand horizontal load-resistance systems. In some cases, the verticalload-resistance system also has some capability to resist horizontal

forces. It is necessary, therefore, to identify the two sources ofresistance and to compare their behavior with respect to the horizontalactions. However, this identification is not that obvious since thebracing is integral within the structure. Some assumptions need bemade in order to define the two structures for the purpose ofcomparison.

Sway Frames vs. Non-Sway FramesThe identification of sway frames and non-sway frames in a building isuseful for evaluating safety of structures against instability. In thedesign of multistory building frame, it is convenient to isolate the

columns from the frame and treat the stability of columns and thestability of frames as independent problems. For a column in a bracedframe, it is assumed that the columns are restricted at their ends fromhorizontal displacements and therefore, are only subjected to endmoments and axial loads as transferred from the frame. It is thenassumed that the frame, possibly by means of a bracing system,satisfies global stability checks and that the global stability of theframe does not affect the column behavior. This gives the commonlyassumed non-sway frame. The design of columns in non-sway framesfollows the conventional beam-column capacity check approach andthe column effective length may be evaluated based on the column

end restraint conditions.

Another reason for defining sway and non-sway frames is the needto adopt conventional analysis in which all the internal forces arecomputed on the basis of the undeformed geometry of the structure.This assumption is valid if second-order effects are negligible. Whenthere is an interaction between overall frame stability and columnstability, it is not possible to isolate the column. The column and theframe have to act interactively in a sway mode. The design of swayframes has to consider the frame subassemblage or the structure as awhole. Moreover, the presence of inelasticity in the columns will

render some doubts on the use of the familiar concept of elasticeffective length

On the basis of the above considerations, a definition can beestablished for sway and non-sway frames as:A frame can be classified as non-sway if its response to in-planehorizontal forces is sufficiently stiff for it to be acceptably accurate to



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A note By P Eng Suraj Singhneglect any additional internal forces or moments arising fromhorizontal displacements of its nodes. This indicates that non swayframe is stronger to resist lateral forces without providing anyother members for such forces. It means that rigidity of frameis higher than its flexibility.

CRC Press LLC Classification of Tall Building FramesA tall building is defined uniquely as a building whose structure createsdifferent conditions in its design, construction and use than those forcommon buildings. From the structural engineers view point, theselection of appropriate structural systems for tall buildings mustsatisfy two important criteria: strength and stiffness. Thestructural system must be adequate to resist lateral andgravity loads that cause horizontal shear deformation andoverturning deformation. Other important issues that must beconsidered in planning the structural schemes and layout are, the

requirements for architectural details, building services, verticaltransportation and fire safety among others. The efficiency of astructural system is measured in terms of its ability to resisthigher lateral loads which increase with the height of theframe. A building can be considered as tall when the effect oflateral loads is reflected in the design. Lateral deflections of tallbuildings should be limited to prevent damage to both structural andnon-structural elements. The accelerations at the top of the buildingduring frequent windstorms should be kept within acceptable limits tominimize discomfort to the occupants.

The various structural systems can be broadly classified into two maintypes:(1) medium height buildings with shear type deformationpredominant and(2) high rise cantilever structures, such as framed tubes, diagonal

tubes, and braced trusses. This classification of system formsis based primarily on their relative effectiveness in resistinglateral loads. At one end of the spectrum is the moment resistingframes which are efficient for buildings of 20 to 30 stories, and atthe other end is the tubular systems with high cantileverefficiency. Other systems were placed with the idea that the

application of any particular form is economical only over alimited range of building heights.

An attempt has been made to develop a rigorous methodology for thecataloging of tall buildings with respect to their structural systems. Theclassification scheme involves four levels of framing division:(1) primary framing system,



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A note By P Eng Suraj Singh(2) bracing subsystem,(3) floor framing, and(4) configuration and load transfer.While any cataloging scheme must address the pre-eminent focus onlateral load resistance, the load-carrying function of the tall building

subsystems is rarely independent. An efficient high-rise system mustengage vertical gravity load resisting elements in the lateral loadsubsystem in order to reduce the overall structural premium forresisting lateral loads.Some degree of independence can be distinguished between the floorframing systems and the lateral load resisting systems but, theintegration of these subassemblies into the overall structural scheme iscrucial.

Composite Floor Systems Semi Rigid Frame up to 15 stories, RigidFrame up to 30 stories, Frame with shear truss up to 45 stories,

Frames with shear bend & outrigger trusses up to 55 stories, Endchannel Framed tubewith interior shear trusses up to 60 stories,End channel & framed tube up to 65 stories, Exterior framedtube up to 85 stories, Bundled framed tube up to 105 stories,Exterior diagonalised tube up to 110 stories

Tall building floor structures generally do not differ substantially fromthose in low-rise buildings; however, there are certain aspects andproperties that need to be considered in design:1. Floor weight to be minimized2. Floor should be able to resist construction loads during the

erection process.3. Integration of mechanical services (such as ducts and pipes) inthe floor zone.4. Fire resistance of the floor system.5. Buildability or constructability of structures.6. Long spanning capability.

Modern office buildings require large floor spans in order to creategreater space flexibility for the accommodation of a greater variety oftenant floor plans. For tall building design, it is necessary to reduce theweight of the floors so as to reduce the size of columns and

foundations and thus, permit the use of larger space. Floors arerequired to resist vertical loads and they are usually supported bysecondary beams. The spacing of the supporting beams must becompatible with the resistance of the floor slabs.

The floor systems can be made worth buildable or worth constructableby using prefabricated or precast elements of steel and reinforced



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A note By P Eng Suraj Singhconcrete in various combinations. Floor slabs can be precast concreteslab, in situ concrete slab or composite slabs with metal decking.Typical precast slabs are 4 to 7m, thus avoiding the need of secondarybeams. For composite slabs metal deck spans ranging from 2 to 7 mmay be used depending on the depth and shape of the deck profile.

However, the permissible spans for steel decking are influenced by themethod of construction in particular, it depends on whether or not,shoring is provided. Shoring is best avoided as the speed ofconstruction is otherwise, diminished for the construction of tallbuildings.

Sometimes openings in the webs of beams are required to permitpassage of horizontal services, such as pipes (for water and gas),cables (for electricity and tele and electronic communication), ducts(air-conditioning), etc.

In addition to strength, floor spanning systems must provide adequatestiffness to avoid large deflections due to live load which could lead todamage of plaster and slab finishers. Where the deflection limit is toosevere, pre-cambering with an appropriate initial deformation equaland opposite to that due to the permanent loads can be employed tooffset part of the deflection. In steel construction, steel members canbe partially or fully encased in concrete for fire protection. For longerperiods of fire resistance, additional reinforcement bars may berequired.

Back Structural Analysis: Gravity and Lateral Loading.

Fundamental PrinciplesStructural analysis is the determination of forces and deformationsof the structure due to applied loads. It involves volumes ofcalculations based on various theories of analysis formulas.Structural design involves the arrangement and proportioning ofstructures and their components in such a way that the assembledstructure is capable of supporting the designed loads within theallowable defined limit states. Analytical model is an idealization ofthe actual structure. The structural model should relate the actualbehavior to material properties, structural details, loading andboundary conditions as accurately as is practicable. In addition,

constructability based on designs plays a significant role.All structures that occur in practice are three-dimensional. Forbuilding structures that have regular layout and are rectangular inshape, it is possible to idealize them into two dimensional framesarranged in orthogonal directions.Joints in a structure are those points where two or more membersare connected.



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A note By P Eng Suraj SinghA trussis a structural system consisting of members that are designedto resist only axial forces.Axially loaded members are assumed to be pin-connected at theirends.A structural system in which joints are capable of transferring

end moments is called a frame. Members in this system areassumed to be capable of resisting bending moment axial forceand shear force. A structure is said to be two dimensional or planarif, all the members lie in the same plane.Beamsare those members that are subjected to bending or flexure.They are usually thought of as being in horizontal positions and loadedwith vertical forces.Ties are members that are subjected to axial tension only, whilestruts (columns or posts) are members subjected to axialcompression only.

Structure formation mechanism should be intuitively conceivedconsidering the possible deflections in all three dimensions. Trialparameters should be used for obtaining various modeling results.Moderation of structure should be conducted prior to making variousanalysis decisions for economizing as well as optimally producing asound, safe & adequate structure. What software or formulae are to beused, is the discretion of the designer. Real purpose of analysis is thatall possible lifetime imposable forces should be covered inconsiderations giving no opportunity to the structure to talk differentlanguage or behave differently than conceived. Structure should becompatible to allow variation of use within certain flexible limits

keeping in view the volume & the cost of building. Contemporaryfashion to be infused into the structure nowadays, is good RCCframing, good shear wall based framing, stronger & flexiblefoundations with good degree of rigidity, energy dissipation techniquesetc. Micro piling, piling, shear keys, structural fills, engineering fills,general fills, sand fills, concrete protections & many others whichrequire equal considerations while analyzing various aspects of thestructure.

Back Structural Design and Ductile Detailing.

Ductility: Capability of a material or structural member to undergolarge inelastic deformations without distress; opposite of brittleness;very important material property, especially for earthquake-resistantdesign; steel is naturally ductile, concrete is brittle but it can be madeductile, if well confined. Ductility takes material into plastic or inelasticstage for allowing it additional deformations without causing structural



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A note By P Eng Suraj Singhfailures. Forces redistribution is carried out in this stage giving anopportunity to structure for safe collapse stage in stages.

Durability: The ability of concrete to maintain its qualities over longtime spans while exposed to weather, freeze-thaw cycles, chemical

attack, abrasion, and other service load conditions. Durable concretedoes not allow rapid chloride penetrations more than defined value.This property leads to prevention from corrosion to acceptable level ifnot fully. It also enhances the service life of concrete & other materials.

Ductility & durability are interrelated terms as one is required toachieve the other. Inducing ductility on to the RCC, durability can beachieved to certain extent by virtue of reinforcing confining actions.

It has already been suggested that, to keep the members ductile,compression reinforcement would assist. It is in the interest of the

structure to produce ductile even if, the member does not technicallyrequire being designed so. Should beam be provided with compressionrebars, it shall help beam ductility even though, the beam has to beprovided rebars in compression zone for purpose of anchorage &temperature rebars.Same principle applies to slabs as well as columns. In fact, within slab,compression steel would also act as reducing the possibility ofdeflection. Rebars would not be required to be cut within the portion ofthe main part of suspended slabs. There shall be no need placeadditional bars on the beams portion in slab for anchorage or negativemoment. Vertical stirrup spacing may be kept confining to the ductile

requirement in case of beams & columns.

Structural design & analysis can be based on any method using anysoftware or by manual means depending on the required quantum ofdesign work. It is also suggested that slab should use smaller dia barsto prevent cracking. Columns should also, not be encouraged by highersize bars. Bars should be tried to be spread on the members surfaces.

Due care should be envisaged for the development length, curtailmentlocations, overlapping considerations & many such required factors.Proper binding should be done in all rebars to keep them fully intact

while pouring concrete. Positions of the construction joints if sorequired, during emergencies, must better be shown on designdrawings. Expansion or contraction joints locations must be indicatedon the drawings so that, these are taken care of by the field engineersto avoid possible mixing of requirement.



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A note By P Eng Suraj SinghDrawings should clearly state the structural brief specification tofacilitate the engineer to understand what should be done on site. Inthe absence of this information, construction site engineer wouldexecute the work complying to his either right or wrong informationjeopardizing the well designed structure. Details should be elaborately

indicated in sections in such a fashion that site engineer does the jobright first time every time. Least queries raisings designate a drawinggood one. If possible, bar bending schedule should be charted outeither on detailed drawings or on some other documents to have theright & accurate cut dimensions. Conventional shape coding based BBSshould be issued for sites execution.

Constructability concerns should be minded while decidingreinforcement within sections of all members. All possible steelcongestion must be avoided. Practical aspects must be minded whiledetailing to extend ease of construction to the site team & the

contractor. Details of required grade of concrete for various locationsas well as grade of reinforcement must all be indicated clearly. Wherewelded prefabricated mesh is to be used, should be clearly mentioned.Totality of project specification must give all information about allrequirements. It is suggested that drawings should accompany someset standard sections for the typical items on the project for reducingthe volumes of detailing repetitions.

Advisory construction method statements though not binding oncontractor or builder, can also be included within the specification toapprise the executor about the project intended requirement.

Definitions of all terms as well as procedures, the relevantspecifications & codes used, should be indicated. Documentsprecedence should be clearly indicated to avoid various disputes.

Back Strength & Retrofitting of Structures & Vulnerability

Assessment:State of building construction in Bharat is not good as far as the quality criteria isconcerned from every angle. Buildings had been constructed long back & have been

being constructed presently but, an overall quality status does not look to be to the

required quality mark. Those structures that were meant to serve for say 50 years, doyield earlier than required & signs of distress & disintegration are visible. Some defects

had been crept in during construction while, the others were by ill use as well as by

adverse weather conditions. There is no gain by criticizing about all these defects but toreinstate or rehabilitate the existing structures to their original state or even to improve

the conditions so that, strucyures can serve up to the designed duration that we call

specified durability.



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A note By P Eng Suraj SinghStructural Audit: The process that involves first understanding the properties losses that

structure has already undergone during its used life by means of testing various materials,

by settlement surveys, by core drillings from RCC without involving reinforcement, bychecking reinforcement conditions etc. all can be termed as structural audit based on

surveys to know the deficiency requirement induced in the structure. If so required, even

the load testing can be conducted on the structures to know about better state of facts.Cores shall definitely tell about the concrete quality while building quality shall be

provided by load testing. Investigation shall reveal about the new requirement, the

structure waits to be rehabilitated for future imposed loads & missing durability. Even, bythis investigation, further life can be added to the structural members. All such

requirements are referred to the process ofrehabilitating & retrofitting the structure.

Retrofitting: It is a slow process which requires high degree of patience & study a lot

about the operations & their research. Substructure as well superstructures would requireretrofitting. Foundations may require extensions. Additional thickness may be required to

be added to foundations. Columns may require jacketing. Beams may require jacketing or

substitute arrangement. Resin injection may be required for the distressed areas. Variouslocations on the concrete surface may require repairs though in patches.

To meet all foregoing requirements, various construction chemicals would be required,

the study of which, the retrofitting engineer should do. Retrofitting covers a wide scope

& varies from one building to another. In some old buildings, structure may be insertedby any method while semi performing buildings could be reinstated to the requirement as

said earlier. Applications of new concrete to the old concrete would be required.

Applications of additional reinforcement to be inserted would also be required. Someweak concrete portions shall be required to be extracted out to be replaced by the new

one. Various combinations of chemicals shall be made necessary. Materials shall be used

based on the recommendations of the chemical supplier or manufacturer as the case maybe. Special chemical concrete, micro concrete, bonding agents, chemical anchors, lowshrinkage concrete & many others would be studied. Intensive research work shall be put

in during investigations. After applying the retrofitting activities, test loads shall be

conducted on all rehabilitated elements. Retrofitting cost factor would dominate overmaking a decision about choosing rebuilding or retrofitting. I think an estimated cost on

retrofitting ranging 30 to 40 % of rebuilding cost should lead to retrofitting.

Preferred Cements: Replaced By Silica fume: Very fine non crystalline silica produced

in electric arc furnaces as a by-product of the production of metallic silicon and varioussilicon alloys (also know as condensed silica fume); used as a mineral admixture in

concrete. GGBS Ground Granulated Blast Furnace Slag. PFA Pulverised Fly Ash

Back Seismic Risk Management in Action:

Post Earthquake-



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A note By P Eng Suraj Singh1. Well, every seismic calamity is different. Disaster level would require what

degree of management is necessary. National Disaster Management authority

should function virtually as a proficient body working with full efficiency & notjust to show its mere presence.

2. Since concrete involves heavy dead loads, heavy duty cranes & other equipment

would be required to remove the broken debris as fast as possible so that somelives could be saved. Various required machines & equipment, mostly

operationally necessary, must be stocked some where all times in all vicinities to

let those be transported to earthquake effected area immediately after the demandis raised.

3. All safety, health & environment issues considerations must be incorporated for

risks mitigation planning or disaster controls bodies. Health authorities must bekept on alerts & be deployed immediately post earthquake occurs. All medicines

& required equipment must be made available with the medical authorities. Many

pools of doctors should be kept on standby to meet such calamities.

4. An easy access to the disaster management personnel & vehicles should be made

available for such disaster management being a success. Specialist personnel mustbe deployed immediately after the earthquake occurrence.

5. Fire can also break out post earthquake which requires fire tender to operate.Emergency buildings such as hospitals, police offices, civil defense,

telecommunications & whatever can serve during such emergencies should be

properly designed keeping in view their required service continuity & if revealeddeficient during audit, must be on priority basis retrofitted.

6. Standby arrangement for water & powers must be made available to meet these

emergencies for certain days or hours till the normal life is reinstated in the area

affected by earthquake.7. All residents of the area susceptible to earthquakes must know how to act during

such moments without causing panic.8. All sequential bye calamities must be well planned to be managed withefficiently. Public should be regularly educated by conducting virtual drills for

awareness teaching about how to conduct in case of earthquake.

Pre Earthquake management requires production of seismic resistant buildings

according to the defined zonings. The design, construction as well as quality criteriashould be complied with come what may. All buildings should be designed &

compulsorily, supervised by certified competent engineers well trained in the buildings &

other structures specific filed. All required facilities should be made intact for the newsettlements. Locations of buildings must be rightly selected so that access & egress for

the involved areas are conveniently effected with. High rise buildings must be allowed

located off from busy roads & colonies. Tall buildings must be provided with allemergency serving measures as applicable to meet successfully all dangers. Local &

central agencies including police as well as army in collaboration with civil defense &

general public should be adequately trained by conducting required drills management &

kept updated.

Back Effect on Natural and Built Environment:



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mailto:[email protected]


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26/35



3 I judged the SBC of the soil to be somewhere 5 to 10 T/sqm basedon my experience yet, it did not meet the building requirement due tounforeseen behaviour of Clays that could have contended minerals likeMontmorillonite or illonite or some others, that could help the soil to swell

while being in contact with water or loosen the entire shear resistance.The proposal was to include one equal size basement that caused me acause of concern. I had decided to avoid the formation of the foundationson existing soil even at cost of additional expenses.

4 Fortunately, I have experienced during my career extensively onthe RCC building projects as well on the industrial on shore projects both,in office engineering as well as field engineering. Based on my experienceearning, I could solve the proposal easily which I did comfortably with fullconfidence successfully. A decision was made to apply soil improvementtechnique in the easiest way so that the bearing capacity as well as the

permeability of the soil below the formation is sustainable. The watershould not effect the foundation if it is allowed to move beneath thefoundation structures. Clay soil had to be isolated from the buildingsubstructures for the purpose of RCC protection.

5 To meet the requirement, I decided to form a road type structurebelow the foundation formation without involving any cementing materialbut to be included just water bound. Some person suggested to use limealso, but it did not convince me as the lime is not a reliable material inmoist environment. I went ahead to excavate about 300 mm additionaldepth to accommodate proposed soil improvement to a minimal meeting.

It could be more thick but, I did not intend to take risk more than that dueto excessive depth of excavation where on two sides, existing building upto three storey are located.

6 The formation was prepared & 40m size aggregate which is calledVapisi in Delhi term, was used to be placed first. 10 mm size aggregatewas placed on the 40 mm size layer so that the voids within the 40 mmsize aggregate be filled with 10 mm size aggregates. Later, the additionallayer of machine graded dust was placed so that the voids within the 10mm size aggregate be filled with the mechanically produced dust. All laiddry mix was watered & compacted just as it is done on a water boundmacadem road structure formation. I noticed after compaction that theformation was very strong & there was much improvement on the SBC.

7 The foregoing fill has to respond to work as a permeable mediumalso for the down flowing water as well as to allow a break for the upwardflowing water in future that could be a result of heavy rains or bywhatsoever reason. This provision has also affected as a barricade for theclay soil to be in contact with the foundations.



27/35



8 In addition to the above, on the sides of the fixed retaining RCCwalls built between the main columns, the fill material used is river sand sothat it allows water to permeability since the clay does not possess thisproperty but considerable porosity. Virtually, the foundations built are soil

contact free & the portions between all the RCC beams foundationsjoining the columns in both directions, an exclusively river sand was usedas a filling material to avoid cumbersome work on compaction of the soilseither to be taken from site or to be imported.

9 I think the work has been done economically in all respectsinducing to the foundation what it necessitated from practical engineeringconstruction viewpoints.

Structural:1 On the prepared soil improvement base, a 50 mm thick layer of

blinding concrete was laid.

2 The surface of the blinding concrete waterproofed using CICOTapecrete coating protected by plastering on the coating.

3 Analysis of the structures done using Kanis Rotation ContributionMethod, a very old method of moment distribution but yet, useful.

4 Analysis of the foundation framed matting done by purpose madeworksheets.

5 The sketch shows the details of the foundation section 400 x 1200mm beam with 800 wide spreader, embedded in full 200 mm thickRCC matting under all the beams in both directions. Columns wererevealed from the beams. One 16000 litres capacity water storagetank has also been provided between the foundation beams.

6 Between the beams, river sand filling provided in place of soil.

7 Externally, 450 mm wide portion filled with river sand whileremaining soil butts with the 450 mm line. There is allowed nocontact between the soil & the foundations anywhere.



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1000.00

400.00

Soil Improvement

Foundation Beam

200.00300.00

Figure 3

8 Retaining walls 200 mm thick provided around the foundations tohold the fill. The wall reinforced with 8 mm rebars @ 200 centresboth ways.

9 Main hall portion allowed 12 columns. 1000 x 400 mm 4 columnswhile 600 x 400 mm 8 columns.

10 Span between the columns 11 m in two frames while 8 m in threeframes.

11 Certain frames are located in the double height area.

12 Front allows 1800 mm wide balconies while sides 1000 mm.

13 Six beams provided in the front balconies at both levels.

14 Main beams permitted 300 mm x 600 mm section for stabilityresolution.

15 Cross beams included 200 x 300 mm section.

16 Stair waste provided 200 mm thick with rebar meshing in top &bottom layers.

17 All suspended slabs included with 8 mm rebars @ 200 mm centresboth top & bottom.



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A note By P Eng Suraj Singh18 ear bed rooms portion constructed with 11 columns 300 mm x 450

mm sections for spans do not exceed 5m.

19 A quantity of 250 cum RCC constructed using M 30/25.All site mixing done.

20 Form support systems employed using rented props.

21 Form material employed 12 mm thick ply & timberscantlings/battens 50 mm x 75 mm & 50 mm x 100 mm.

22 A total quantity of rebars used 22000 kg.Up to ground level 8000 kg & above ground 14000 kg.

23 Labour contractor did not include curing element consequently Ihad to do this part myself. I did not find any problem for the

suspended slab curing but for the columns & brick walls, I faced thehard job.

24 Though the proposed use of the building is for the residentialpurpose as per local authority, yet the visitors put the building notas residential in look but either commercial or any office.

Observations:1 I tried all efforts to extract a good quality of the structure from the

workers used to system in NCR but, I was successful to certainextent only. It necessitates a lot of training to be imparted with the

skilled workers as well as the self styled contractors & foreman.Most significant part that requires training is about what should bereal procedures of producing, transporting & placing concrete mixwithin right defined duration. QA system is slackening on the use ofstructural concrete. Generally, RMC suppliers think that cuberesults only dominate the concrete. There is no call in Bharat Indiato mandatory drill cores post concreting to ensure the accuracy orgenuine sampling of cubes.

2 Concrete pouring gangs do work efficiently but, compliance with therequirement raises a question mark on various projects. Absence ofqualified engineers on the supervision also raises eyebrows. Publicseems to be ignorant & non serious about the required quality ofgood concrete & very few understand the durability of concrete as abasic property. What is seen by eyes is considered building workbut, real technological requirements do not reach the builder or thegeneral public. Promoters or builders befool the consumers in thename of international standards & make profits from innocentbuyers.



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Right Elevation

FOR Submission

OWNERS- SURAJ SINGH & SUMITRA

PLOT 430/1A, SECTOR 21B, FARIDABAD-HUDA AREA

ElevationArchitectural

2500

1625

3250

3250

2125

500

750

3250

3250

300

300

300

875

100

525

738

437

525 595297297297297

594 475 475 475 475

738

738

738

737

3.24

2.35

8.85 sqm

1.37

3.4

3.0

1.56

Figure 4

OWNERS-SURAJSINGH&SUMITRA

PLOT430/1A,SECTOR21B,FARIDABAD-HUDAAREA

FORSubmission

Left Elevation

Elevation

Architectural

2000

3750

3250

3250

500

3250

3250

3250

1000

2000

1250

300



31/35


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A note By P Eng Suraj SinghFigure 7

Foundations Beams Rebars Plan

1

4

5

3

2

A B C D

4

3

5

B

1

2

A C D

1000

2472

2300

2777

2499

6 / 16 each in 3 l ayer s 6 / 16 i n 1 l ayer, 4 other layer4 Legged/8 rings @200 c/c

4 / 1 2 ea ch i n 2 l ay er s 6 / 1 2 ea ch i n 3 l ayer s 4 L eg ge d/ 8 r in gs @ 20 0 c /c

4 / 1 2 ea ch i n 2 l ayer s 6 / 1 2 e ac h i n 2 l ayer s 4 L egg ed/ 8 r in gs @ 20 0 c/ c 6 / 12

6 / 12 6 / 1 6 e ac h i n 3 l ay er s 4 L eg ge d/ 8 r i ng s @ 20 0 c /c 4 / 1 2 i n 2 l ay er s

6 / 12 6 / 1 6 e ac h i n 3 l ay er s 4 L eg ge d/ 8 r i ng s @ 20 0 c /c 4 / 1 2 i n 2 l ay er s

6/12in1layer,4inanotherr

6/12in1layer

4/12in1layer

6/12in1layer

6/16eachin3layers

6/16eachin3layers

6/12eachin3layers

6/12in1layer,4otherlayer

6/16eachin3layers

6/16eachin4layers

6/12eachin3layers

Typical

200

100

200

200

200

300

400

200

800

6 / 12 each in 3 l ayers



33/35


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A note By P Eng Suraj Singhdetermination, dedication, commitment, implementation, postimplementation scrutiny or audits, are all a must & must be seen dulyperforming in addition to approved or recognized agreements. Bare talks& statements would not work to give required results. Real action must beseen doing by one & by all members of all departments teams.

No leniency should be accepted on doing any activity to the requirement inany department or section. Safety first & Quality must attitude must beadopted as a strong potential slogan. Since world has been changing thenBharat / India has to change otherwise, there would be no way to escapefrom due responsibility & legal liability.

-----------------------------------------------------------------------------------------------------------

-

Thanks a Lot Indeed for your Patience & Kind Attention. Sorry for

boring you by long descriptive contents.

P Eng Suraj Singh------------------------------------------------------------------------------------------------------------

May we browse following links?

Various Engineers Responsibilities Role of Site Engineer Based

Training Talks Training Brief (Extracts)

Government Involvement Brainstorming Slides

Earthquake Risk Management EQ Management Initiatives

Building a Techno Legal Regime For Safer Bharat / India

knowledge-manageme Knowledge Portal

Engineers Updating EQ National Programme

National Disaster Management Authority Body

..\NDM\Simplified Guideline_Zone III.pdf EQ Provisions

..\NDM\Simplified Guideline_Zone IV.pdf EQ Provisions

http://opt/scribd/conversion/tmp/scratch17710/EQ%20management%20Role%20of%20Site%20Engineers.dochttp://opt/scribd/conversion/tmp/scratch17710/Chapters%20Building%20Safety%20From%20Natural%20Hazards.dochttp://opt/scribd/conversion/tmp/NDM/Brainstorming%20Session.ppthttp://opt/scribd/conversion/tmp/NDM/EARTHQUAKE%20RISK%20MANAGEMENT.ppthttp://opt/scribd/conversion/tmp/NDM/Building%20a%20Techno%20Legal%20Regime.pdfhttp://opt/scribd/conversion/tmp/NDM/knowledge-manageme.pdfhttp://opt/scribd/conversion/tmp/NDM/NPCBEERM.pdfhttp://opt/scribd/conversion/tmp/NDM/URL%20Ref.dochttp://opt/scribd/conversion/tmp/NDM/Simplified%20Guideline_Zone%20III.pdfhttp://opt/scribd/conversion/tmp/NDM/Simplified%20Guideline_Zone%20IV.pdfmailto:[email protected]://opt/scribd/conversion/tmp/scratch17710/EQ%20management%20Role%20of%20Site%20Engineers.dochttp://opt/scribd/conversion/tmp/scratch17710/Chapters%20Building%20Safety%20From%20Natural%20Hazards.dochttp://opt/scribd/conversion/tmp/NDM/Brainstorming%20Session.ppthttp://opt/scribd/conversion/tmp/NDM/EARTHQUAKE%20RISK%20MANAGEMENT.ppthttp://opt/scribd/conversion/tmp/NDM/Building%20a%20Techno%20Legal%20Regime.pdfhttp://opt/scribd/conversion/tmp/NDM/knowledge-manageme.pdfhttp://opt/scribd/conversion/tmp/NDM/NPCBEERM.pdfhttp://opt/scribd/conversion/tmp/NDM/URL%20Ref.dochttp://opt/scribd/conversion/tmp/NDM/Simplified%20Guideline_Zone%20III.pdfhttp://opt/scribd/conversion/tmp/NDM/Simplified%20Guideline_Zone%20IV.pdfmailto:[email protected]


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