Comparative Study on RCC Structure with and Without Shear

Wall at different locations

Abstract

Earthquake resistant structures are the need of time. Today the billion dollar construction

industry has a made a landmark in the history with super high rise buildings viz. Burj Khalifa

(829.8m). Such tall structures need a high resistance to the horizontal loads of wind forces and

seismic forces. To construct these modern mammothic structures Structural engineers have laid

great efforts in the development of techniques for the anti-seismic design of structures. One

such method is the use of RCC Shear wall. Shear walls have proved to be a very useful, reliable

and effective method for earthquake resistance.

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1. INTRODUCTION

Reinforced concrete shear wall structures wide space in many earthquake regions, Such as

India, Canada, Turkey and Chile. Shear walls are vertical elements of horizontal force resisting

system. They are usually provided in tall buildings to avoid the total collapse of buildings under

seismic forces. Shear wall buildings are usually regular in plan and elevation. Shear walls are

usually provided between columns, stairwells, lift wells, toilets, and utility shafts. When shear

walls are situated in advantageous positions in a building, they can be very efficient in restating

lateral loads originating from wind or earthquakes. Huge lateral loads acting on structural

elements results in shear; in order to overcome shear for a building shear wall is provided. RC

buildings with shear wall also have columns; these columns primarily carry gravity loads. RCC

shear walls classifications are bar bell type shear wall, coupled shear wall, rigid frame shear

wall, column supported shear wall sand core type shear wall. Out of this shear walls rectangle

type shear wall, core type shear wall, and coupled type shear walls are used for analysis.

Rectangular type shear wall are formed by columns and walls in between. Core type shear walls

have good resistance to torsion. So many Literatures are available for design of RCC shear

walls. However less discussion about the location of shear wall and suitable type of shear wall

for RCC buildings. More shear walls are uneconomical in low earthquake intensity areas. Shear

wall should be provided suitable position to resist the lateral forces. Some times more number

of shear walls is not economic. Shear walls are provided proper location in the building and

reduce the collapse of structure.

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2. Definition

Shear walls are vertical elements of the horizontal force resisting system. Shear walls are

constructed to counter the effects of lateral load acting on a structure. In residential

construction, shear walls are straight external walls that typically form a box which provides all

of the lateral support for the building. When shear walls are designed and constructed properly,

and they will have the strength and stiffness to resist the horizontal forces. In building

construction, a rigid vertical diaphragm capable of transferring lateral forces from exterior

walls, floors, and roofs to the ground foundation in a direction parallel to their planes. Examples

are the reinforced-concrete wall or vertical truss. Lateral forces caused by wind, earthquake, and

uneven settlement loads, in addition to the weight of structure and occupants; create powerful

twisting (torsion) forces. These forces can literally tear (shear) a building apart. Reinforcing a

frame by attaching or placing a rigid wall inside it maintains the shape of the frame and prevents

rotation at the joints. Shear walls are especially important in high-rise buildings subjected to

lateral wind and seismic forces. In the last two decades, shear walls became an important part of

mid and high-rise residential buildings. As part of an earthquake resistant building design, these

walls are placed in building plans reducing lateral displacements under earthquake loads. So

shear-wall frame structures are obtained.

Shear wall buildings are usually regular in plan and in elevation. However, in some buildings,

lower floors are used for commercial purposes and the buildings are characterized with larger

plan dimensions at those floors. In other cases, there are setbacks at higher floor levels. Shear

wall buildings are commonly used for residential purposes and can house from 100 to 500

inhabitants per building

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3. Scope of the work

The aim of the shear wall is to investigate the different ways in which the tall structures can be

stabilized against the effects of strong horizontal wind loading and seismic loading. Some other

reasons why we use shear walls are tall structures can be constructed which reduces the area

used and we can accommodate a large population in that particular area. Other objective is to

construct a cost effective structure in less period of time. This study helps in the investigation of

strength and ductility of walls. The scope is to analyze the constructed shear wall that is to be

constructed. Firstly the model is implemented into known computer software and then it is

analyzed based on the investigation of strength and ductility. The strength of shear walls tested

are compared with the calculated strengths based on design codes. Shear walls in high seismic

regions require special detailing. However, in past earthquakes, even buildings with sufficient

amount of walls that were not specially detailed for seismic performance (but had enough well-

distributed reinforcement) were saved from collapse. Shear wall buildings are a popular choice

in many earthquake prone countries, like Chile, New Zealand and USA. Shear walls are easy to

construct, because reinforcement detailing of walls is relatively straight-forward and therefore

easily implemented at site. Shear walls are efficient, both in terms of construction cost and

effectiveness in minimizing earthquake damage in structural and non- structural elements (like

glass windows and building contents). Most RC buildings with shear walls also have columns.

These columns primarily carry gravity loads (i.e., those due to self-weight and contents of

building).Shear walls provide large strength and stiffness to buildings in the direction of their

orientation, which significantly reduces lateral sway of the building and thereby reduces damage

to structure and its contents.

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4. Types of Structures

1 Braced structures

2 Unbraced structures

3 Dual structures

As shown in in all the three cases , the resistance to gravity loads (DL+LL) is provided

invariably by beam column and space frames. However, they differ in carrying horizontal loads.

Braced, unbraced and dual structures are briefly described as follows:

4.1 Braced structures

A typical braced frame is shown in figure. In braced frames the lateral loads like wind

earthquake etc, are resisted by special arrangements like shear walls, shear trusses, bracing or

special supports. Thus the beam column frames are not subjected to horizontal loads. In other

words the sidesway or joint translation is not possible in column. The structure is called a

braced structure and columns occurring in such structure are called the braced column.

The shear walls, shear trusses or bracing provided in the building must have stiffness to act as

effective bracings. According to SP: 24 the bracing system must provide a total stiffness equal

to at least six times the sum of stiffness of all the columns, within the storey. They may become

uneconomical for larger height as shear walls are designed as vertical cantilevers from the

ground.

4.2 Unbraced structures

A typical unbraced frame is shown in figure, where resistance to horizontal loads is provided by

bending in the beam and column in that plane. In other words, the sidesway or joint translation

do occur in such frames. These structures are called unbraced structures and the columns

occuring in such structures are called unbraced columns.

4.3 Dual structures

Dual structures are combination of the above two. The resistance to horizontal loads is provided

by both, the bending in frames and by shear walls. The frames and shear walls will resist

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horizontal forces in proportion to their relative stiffness . However, the frame should be

designed to carry minimum 25% horizontal shear.

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5. Loads on Structure

5.1. Vertical Loads

Structurally speaking, buildings are built to support loads. The load, which is ever present and

ever acting on a building, is the dead load which consists of the self-weight of member, finishes,

plaster, etc. Dead load should be calculated very accurately, as it comprises most of the building

load. IS: 1911-1967 gives schedule of unit-weights of building materials and it is used

extensively to calculate the dead load.

Next in importance to dead load, is the live load, which is caused by the use of building. Live

loads are given in IS: 875.

Live loads are generally high (150 kg/m2 to 1500 kg/m2) on floors depending on the activity that

is carried on there, while it is of a low value (75 kg/m2 to 150 kg/m2) on a roof, which may or

may not be accessible. Snow loads on roofs in hilly areas are also specified in IS: 875. In snow-

incident areas, roofs are to be made sloping due to snow at 2.5 kg/m2 per cm depth of snow.

With 30 cm snow depth, the snow loading will work out to be 75 kg/m2, which may be

reasonable for sloping roofs.

Partition loads are also important to be considered. Wooden or similar light-weight partitions

anywhere on a floor give a general loading of 100 kg/m2 of floor area. But in most of the

buildings, brick walls are arranged to divide space, which gives a heavier loading on the floor.

IS: 875 gives the partition walls loading at one-third the weight of 1.0 m run of the partition

wall. \

Thick brick walls anywhere add substantially to the building and it affects the design of slabs,

beams, columns and footings too. But in the present practice, for flexibility in the use of the

building, this provision is made in most of the buildings and wherever possible, brick walls

should be replaced by wooden partitions to achieve in lighter partition loading, which finally

leads to economy in structural design. In practice, wooden partitions are provided in office

buildings, while in hospitals and institutional buildings, brick walls are used as partition walls.

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5.2. Temperature and shrinkage loading

Temperature and shrinkage also act on a building and these can also be regarded as a load on it.

Shrinkage is equivalent to -15 0C, where negative stands for fall of temperature . The

temperature differential is taken at ± 17 2/3(t1-t2), where t1 and t2 are the maximum and the

minimum temperatures observed in a day (24 hours) for a given place or locality . Fall of

temperature together with shrinkage will govern the design, while the rise of temperature will

be substantially reduced in effect by the Indian Road Congress at ±17 0C for moderate climates

and at ±25 0C for extreme climates. The combined effect of temperature and shrinkage is given

below.

For moderate climates : ± 17 - 15 = +2, - 32 (0C)

For extreme climates : ± 25 - 15 = +10, - 40 (0C)

IS: 456 1978 (hereafter called simply that Code) states in its clause number 17.5.1 that “in

ordinary buildings, effect due to temperature fluctuations and shrinkage and creep can be

ignored in the design calculations”. It is, however, not explained, what is meant by an ordinary

building. It is, Of course, it is clear that temperature and shrinkage loading has an effect on the

design of long concrete buildings, which can be neglected if the length of building is restricted

to 45 m (clause 26.3 of the Code). Thus, it can be summarized that temperature and shrinkage

effect can be neglected in short-length buildings. It is also seen that by providing minimum

specified steel percentages in concrete members, temperature and shrinkage effects can be

absorbed in short-length buildings, while in long concrete buildings, these members have to be

designed for this extra loading or a long building has to be cut up in two or more short-length

buildings. Further, this loading can be made use of in the evaluation of the gap of an expansion

joint.

5.3. Wind loading

Dead and live loads are vertical or gravity loads. While wind and earthquake cause horizontal

loads on a building. Temperature and shrinkage also results in horizontal loads on a building.

Blast effect, earth and water pressure also a horizontal loads on a structure . IS:875 gives values

of wind pressure varying from 100kg/m2 acting on building up to a height of 30m above the

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mean retarding surface i.e. the mean level of the adjoining ground . For buildings of height up

to 10.0m, these wind pressure values can be reduced by 25 %.

5.4. Earthquake loading

IS 1893:2002 Criteria for earthquake resistant design of structures part 1 general provisions and

buildings

The Code is now split into five parts

Part 1 - General provisions and buildings

Part 2 - Liquid retaining tanks - Elevated and ground supported

Part 3 - Bridges and retaining walls

Part 4 - Industrial structures including stack like structures

Part 5 - Dams and embankments

Part 1 contains provisions that are general in nature and applicable to all structures. Also, it

contains provisions that are specific to buildings only. The important changes as compared to IS

1893:1984 are as follows:

1. Seismic zone map is revised with only four seismic zones. Zone I is upgraded to Zone II.

Killari area is enhanced to Zone III. Bellary isolated zone is removed. East coast is enhanced to

Zone III and connected with Zone III of Godavari Graben area.

2. Seismic zone factor is changed reflecting a more realistic value of peak ground acceleration.

3. Response acceleration spectra are now specified for three types of founding strata viz. Hard,

Medium and Soft.

 

4. The empirical formula for calculating fundamental natural period T=0.1h for moment

resisting frames without bracing or shear walls is replaced with

Ta=0.075h0.075

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For RC framed buildings, this formula applies to bare frames e.g. in industrial plant buildings.

The formula for framed buildings with in-filled masonry walls is Ta = 0.09h/d0.5 where h and d

are the height and base dimension of the building along the considered direction of earthquake.

5. Revised procedure first calculates the actual force that may be experienced by the structure

during the probable maximum earthquake, if it were to remain elastic. Then response reduction

due to ductile deformation or frictional energy dissipation in the cracks is applied via response

reduction factor R in place of the earlier performance factor K. The list of building systems and

the corresponding values of R is more exhaustive.

The code procedures for calculating base shear VB are summarized below:

 

IS:1893-2002

V B=Ah W

 

Ah=¿¿

 

Z = Zero period acceleration value for the Maximum Considered Earthquake

Zone II III IV V

Z 0.10 0.16 0.24 0.36

  

Sa/g

= Spectral acceleration coefficient for Hard, Medium or Soft soil, 5% damping

= 2.5 for T <= 0.40 and 1.00/T for T > 0.40 (Hard: GP,GW,SP,SW,SC with N>30)

= 2.5 for T <= 0.55 and 1.36/T for T > 0.55 (Medium: All with 10<N<30 SP with N>15)

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= 2.5 for T <= 0.67 and 1.67/T for T > 0.67 (Soft: All except SP with N<10)

I = Importance factor

= 1.5 for hospitals, schools, cinema halls, monumental structures, telephone exchanges,

television, radio, fire, railway power stations and 1.0 for others 

R = Response reduction factor

Ordinary RC Moment Resisting Frame (OMRF) 3

Special RC Moment Resisting Frame (SMRF) 5

Ordinary RC Shear Walls 3

Ductile RC Shear Walls 3

Dual Systems with frames carrying >25% of VB

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6. LITERATURE REVIEW

Introduction

Reinforced concrete structural walls are important components of lateral load resisting systems

in a multistoried building. Due to their high lateral stiffness, the walls restrict the deformation

response of buildings under lateral loads, thereby reducing the nonstructural damage of the

building at the same time. Wall sections, which are designed and detailed for seismic forces, can

achieve sufficient ductility and ensure good hysteretic response of the building system during

earthquakes.

6.1 Classification of shear wall

6.1.1. Classification according to shape

Shear walls are oblong in cross-section,i.e., one dimension of the cross-section is much larger

than the other. While rectangular cross-section is common, L- and U-shaped

sections are also used . If the columns are provided at the edge of the wall,these columns are

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known as boundary elements .Thin-walled hollow RC shafts around the elevator core of

buildings also act as shear walls, and should be taken advantage of to resist earthquake forces.

6.1.2.Classification according to Height – to-Width ratio

a. Slender Shear wall

hw

>2

b. Squat Shear wall

hw

< 12

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7. Failure Modes

7.1 Failure modes in slender walls

Slender walls are governed by their flexural strength. They are subjected to low nominal shear

stress. They develop a predominantly horizontal crack pattern in the lower hinging region after a

few cycles of inelastic deformation.. After yield of the vertical reinforcement, shear is resisted

by

interface friction across the crack and dowel action of the vertical reinforcement. The flexural

strength of such walls is limited by fracture of main flexural reinforcement that is provided near

the wall edges concrete crushing in the compression zone, or lateral instability of the

compression zone (Fig 2.3) Fracture of the main flexural reinforcement takes place due to low

cycle fatigue caused by alternate tensile yielding and inelastic compressive buckling of the bars.

Bauschinger effect also makes the compression steel buckle earlier than in comparable

monotonically loaded specimens. The provisions of adequate transverse confining

reinforcement to the main flexural reinforcement near the outer edges of the wall and in

boundary elements can delay the onset of buckling.It will also contain the cracked concrete and

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prevent it from falling away thereby preventing loss of lateral support to the main flexural

reinforcement.

Failure due to concrete crushing occurs when the crushing strain of concrete is exceeded

in the compression zone of the wall. This is usually accompanied by buckling of the main

flexural reinforcement. Wall sections are usually under-reinforced and so concrete crushing is

not expected. However such a failure can occur in rectangular walls that have a large percentage

of vertical reinforcement and carry a large axial load. Unsymmetrical wall sections, such as T,

L, etc are heavily stressed in the compression zone and may also fail by this mode.

Reversed loading may cause the effective moment of inertia of the wall section to reduce

to that of steel area alone. This will reduce stability of the wall against out of plane

displacements and may cause lateral buckling of the compression zone.

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8. STAAD PRO MODELING AND PROPOSED WORK

The modelS of structure, without and with shear wall are shown in here. The beam elements

and surface elements are used for modeling purpose of structure. The surface element is used

for the modeling of shear wall. Details of number of nodes, beam elements, and Surface

elements are outlined.

In the present work the seismic analysis of a multistorey building with shear wall and

without shear wall will be presented. . Analyses for live load, dead load, earthquake load and

various load combinations will be done using software STAAD PRO. The steps involving

analysis of shear wall for different location in the structure will be presented. The Preferred

locations of the shear walls for the work will be taken at boundry, at lift well and at opposite

ends.

8.1. About STAAD PRO

STAAD or (STAAD.Pro) is a structural analysis and design computer program originally

developed by Research Engineers International in Yorba Linda, CA. In late 2005, Research

Engineer International was bought by Bentley Systems.

The commercial version STAAD.Pro is one of the most widely used structural analysis and

design software. It supports several steel, concrete and timber design codes.

It can make use of various forms of analysis from the traditional 1st order static analysis, 2nd

order p-delta analysis, geometric non linear analysis or a buckling analysis. It can also make use

of various forms of dynamic analysis from modal extraction to time history and response

spectrum analysis.

In recent years it has become part of integrated structural analysis and design solutions mainly

using an exposed API called OpenSTAAD to access and drive the program using an VB macro

system included in the application or other by including OpenSTAAD functionality in

applications that themselves include suitable programmable macro systems. Additionally

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STAAD.Pro has added direct links to applications such as RAM Connection and STAAD.

Foundation to provide engineers working with those applications which handle design post

processing not handled by STAAD.Pro itself.

Structure without shear wall

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19

Structure with shear wall

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9. SHEAR WALLS (IS 13920:1993 RECOMMENDATIONS)

General Requirements

9.1.1 The requirements of this section apply to the shear walls, which are part of the lateral

force resisting system of the structure.

9.1.2 The thickness of any part of the wall shall preferably, not be less than 150 mm.

9.1.3 The effective flange width, to be used in the design of flanged wall sections, shall be

assumed to extend beyond the face of the web for a distance which shall be the smaller of

(a) half the distance to an adjacent shear wall web, and

(b) l/1O th of the total wall height.

9.1.4 Shear walls shall be provided with reinforcement in the longitudinal and transverse

directions in the plane of the wall. The minimum reinforcement ratio shall be 0.0025 of the

gross area in each direction. This reinforcement shall be distributed uniformly across the cross

section of the wall.

9.1.5 If the factored shear stress in the wall exceeds 0.25 √ fck or if the wall thickness exceeds

200 mm, reinforcement shall be provided in two curtains, each having bars running in the

longitudinal and transverse directions in the plane of the wall.

9 1.6 The diameter of the bars to be used in any part of the wall shall not exceed l/1O th of the

thickness of that part.

9.1.7 The maximum spacing of reinforcement in either direction shall not exceed the smaller of

lw/5, 3tw, and 450 mm; where lw is the horizontal length of the wall, and tw is the thickness

of the wall web.

9.2 Shear Strength

9.2.1 The nominal shear stress, τv shall be calculated as:

Where

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VU = factored shear force,

tw = thickness of the web, and

dw= effective depth of wall section.

This may by taken as 0.8 lw, for rectangular sections.

9.2.2 The design shear strength of concrete, Q, shall be calculated as per Table 13 of IS 456 :

1978.

9.2.3 The nominal shear stress in the wall, τv, shall not exceed τc, max, as per Table 14 of IS

456 : 1978.

9.2.4 When τv is less than τc shear reinforcement shall be provided in accordance with 9.1.4

9.1.5 and 9.1.7.

9.2.5 When τv is greater than τc, the area of horizontal shear reinforcement, Ah to be provided

within a vertical spacing. Sv is given by

Vus = 087 × f y× A h× d w

Sv

where

Vus = ( Vu - τc tw dw ),

is the shear force to be resisted by the horizontal reinforcement. However, the amount of

horizontal reinforcement provided shall not be less than the minimum, as per 9.1.4.

9.2.6 The vertical reinforcement, which is uniformly distributed in the wall, shall not be less

than the horizontal reinforcement calculated as per 9.2.5.

9.3 Flexural Strength

9.3.1 The moment of resistance, Muv, of the wall section may be calculated as for columns

subjected to combined bending and axial load as per IS 456 : 1978. The moment of resistance

of slender ,rectangular shear wall section with uniformly distributed vertical reinforcement is

given in Annex A.

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9.3.2 The cracked flexural strength of the wall section should be greater than it’s untracked

flexural strength.

9.3.3 In walls that do not have boundary elements, vertical reinforcement shall be concentrated

at the ends of the wall. Each concentration shall consist of a minimum of 4 bars of 12 mm

diameter arranged in at least 2 layers.

9.4 Boundary Elements

Boundary elements are portions along the wall edges that are strengthened by longitudinal and

transverse reinforcement. Though they may have the same thickness as that of the wall web

it is advantageous to provide them with greater thickness.

9.4.1 Where the extreme fibre compressive stress in the wall due to factored gravity loads plus

factored earthquake force exceeds 0.2fck, boundary elements shall be provided along the

vertical boundaries of walls. The boundary, elements may be discontinued where the calculated

compressive stress becomes less than 0.15fck. The compressive stress shall be calculated using

a linearly elastic model and gross section properties.

9.4.2 A boundary element shall have adequate axial load carrying capacity, assuming short

column action, so as to enable it to carry an axial compression equal to the sum of factored

gravity load on it and the additional compressive load induced by the seismic force. The latter

may be calculated as:

Mu−M uv

Cw

Where:

Mu = factored design moment on the entire wall section,Muv = moment of resistance provided by distributed vertical reinforcement across the wall section Cw = center to center distance between the boundary elements along the two vertical edges of the wall.

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9.4.3 If the gravity load adds to the strength of the wall, its load factor shall be taken as 0.8.

9.4.4 The percentage of vertical reinforcement in the boundary elements shall not be less than

0.8 percent, nor greater than 6 percent. In order to avoid congestion, the practical upper limit

would be 4 percent.

9.4.5 Boundary elements, where required, as per 9.4.1, shall be provided throughout their

height, with special confining reinforcement, as per 7.4.

9.4.6 Boundary elements need not be provided, if the entire wall section is provided with special

confining reinforcement, as per 7.4.

9.5 Coupled Shear Walls

9.5.1 Coupled shear walls shall be connected by ductile coupling beams. If the earthquake

induced shear stress in the coupling beam exceeds is

0.1× ls √ f ck

D

where ls is the clear span of the coupling beam and D is its overall depth, the entire earthquake

induced shear and flexure shall, preferably, be resisted by diagonal reinforcement.

9.5.2 The area of reinforcement to be provided along each diagonal in a diagonally reinforced

coupling beam shall be:

Vu

1.74 × f y × sinα

where Vu is the factored shear force, and α is the angle made by the diagonal reinforcement with

the horizontal. At least 4 bars of 8 mm diameter shall be provided along each diagonal. The

reinforcement along each diagonal shall be enclosed by special confining reinforcement, as per

7.4. The pitch of spiral or spacing of ties shall not exceed 100 mm.

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9.5.3 The diagonal or horizontal bars of a coupling beam shall be anchored in the adjacent

walls with an anchorage length of 1.5 times the development length in tension.

9.6 Openings in Walls

9.6.1 The shear strength of a wall with openings should be checked along critical planes that

pass through openings.

9.6.2 Reinforcement shall be provided along the edges of openings in walls. The area of the

vertical and horizontal bars should be such as to equal that of the respective interrupted bars.

The vertical bars should extend for the full storey height. The horizontal bars should be

provided with development length in tension beyond the sides of the opening.

9.7 Discontinuous Walls

Columns supporting discontinuous walls shall be provided with special confining

reinforcement, as per 7.4.4.

9.8 Construction Joints

The vertical reinforcement ratio across a horizontal construction joint shall not be less than:

.92fy

(τ v−Pu

A g

)

where Tv is the factored shear stress at the joint, Pu, is the factored axial force ( positive for

compression ), and Ae is the gross cross sectional area of the joint.

9.9 Development, Splice and Anchorage Requirement

9.9.1 Horizontal reinforcement shall be anchored near the edges of the wall or in the confined

core of the boundary elements

9.9.2 Splicing of vertical flexural reinforcement should be avoided, as far as possible, in regions

where yielding may take place. This cone of flexural yielding may be considered to extend for a

distance of lw above the base of the wall or one sixth of the wall height, whichever is more.

However, this distance need not be greater than 2lw. Not more than one third of this vertical

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reinforcement shall be spliced at such a section. Splices in adjacent bars should be staggered by

a minimum of 600 mm.

9.9.3 Lateral ties shall be provided around lapped spliced bars that are larger than 16 mm in

diameter. The diameter of the tie shall not less than one fourth that of the spliced bar nor less

than 6 mm. The spacing of ties shall not exceed 150 mm center to center.

9.9.4 Welded splices and mechanical spliced bars that are larger than 16 mm. The spacing of

ties shall confirm to 25.2.5.2 of IS 456 : 1978. in diameter. The diameter of the tie shall not

However, not more than half the reinforcement be less than one fourth that of the spliced bar

shall be spliced at a section, where flexural nor less than 6 mm. The spacing of ties shall

yielding may take place.

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References

1. ______Indian Standard Code of Practice for Plain and Reinforced Concrete, IS

456:1978.Bureau of Indian Standards, New Delhi.

2. ______Indian Standard Code of Practice for Plain and Reinforced Concrete, IS 456:2000

Bureau of Indian Standards, New Delhi.

3. Indian Standard Code of Practice for Ductile Detailing of Reinforced Concrete Structures

subjected to Seismic Forces, IS 13920: 1993. Bureau of Indian Standards, New Delhi.

4. ______ Indian Standard Code of Practice for Structural Safety of Buildings: Loading

Standards, IS:875-1964. Bureau of Indian Standards, New Delhi.

5. ______ Indian Standard Criteria for Earthquake Resistant Design of Structures

IS1893:2002. Bureau of Indian Standards, New Delhi.

6. ______ Explanatory Handbook on Indian Standard Code of Practice for Plain and

Reinforced Concrete (IS: 456-1978), SP: 24-1983, Bureau of Indian Standards New Delhi.

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