ANALYSIS OF SHEAR WALL DUE TO LATERAL LOAD.docx

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ANALYSIS OF SHEAR WALL DUE TO LATERAL LOAD

A Project Report Submitted to the Department of Civil Engineering of

World University Of Bangladesh in Partial Fulfillment of the

Requirements for the Degree of Bachelor

Of

Science in Civil Engineering

Submitted By

MD. ABUL KASHEM

Reg: WUB 10/08/23/635

MD. ZAHIRUL HOQUE

Reg: WUB 10/08/23/636

MD. MASUD RANA

Reg: WUB 10/08/23/639

MD. ABDUL BATEN

Reg: WUB 10/08/23/623

RANZU AHMED

Reg: WUB 10/08/23/637

Supervisor

NOVEMBER 2012

AHMED SHIBLEE NOMAN

Assistant Professor

Department of Civil EngineeringWorld University of Bangladesh.

S M TANVIR FAYSAL ALAM

CHOWDHOURY

LecturerDepartment of Civil Engineering

World University of Bangladesh.


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LETTER OF TRANSMITTAL

November 2012

To

Ahmed Shiblee Noman

Assistant Professor

Department of Civil Engineering


Subject: Submission of Project Report.

Sir,

We are pleased to submit hereby the project report on Analysis of shear wall due to

lateral load .It was great pleasure to work on such an important topic. This project

report has been prepared according to the requirement of the World University of

Bangladesh,

We are pleased that this report will certainly help you in evaluating our project report on

Analysis of shear wall due to lateral load. We would be very happy to provide any

assistance in interpreting any part of the report whenever necessary.

Thanking You.

Sincerely yours,

RANZU AHMED

Reg: WUB 10/08/23/637

MD. ZAHIRUL HOQUE

Reg: WUB 10/08/23/636

MD. MASUD RANA

Reg: WUB 10/08/23/639

MD. ABDUL BATEN

Reg: WUB 10/08/23/623

MD. ABUL KASHEM

Reg: WUB 10/08/23/635


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DECLARATION

We hereby, solemnly declare that the work presented in the project report has been

earned out by us and so far known, none has yet submitted this type of work in any

University, College and Organization for an academic qualification.

We hereby guarantee and ensure that the work has been presented by us, does not breach

any existing copyright.

We, further, undertake to indemnify the University against any loss or damage arising

from breach of the for the foregoing obligation,

RANZU AHMED

Reg: WUB 10/08/23/637

MD. ZAHIRUL HOQUE

Reg: WUB 10/08/23/636

MD. MASUD RANA

Reg: WUB 10/08/23/639

MD. ABDUL BATEN

Reg: WUB 10/08/23/623

MD. ABUL KASHEM

Reg: WUB 10/08/23/635


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World University of Bangladesh (WUB)

CERTIFICATION

This is the certify that the project on ANALYSIS OF SHEAR WALL DUE TO

LATERAL LOAD, is an authentic and bonafide record of the project work done by

Md. Abdul Baten, Md. Masud Rana, Ranzu Ahme, Md. Zahirul Haque, and Md. Abul

Kashem for partial fulfillment of the requirement for the degree of B. Sc in Civil

Engineering from the World University of Bangladesh (WUB) .

This project work has been carried out under my guidance and is a record of successful

work.

Faculty Guide.

Ahmed Shiblee NomanAssistant Professor

Department of Civil Engineering



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ACKNOWLEDGEMENT

All parses for the Almighty Allah, the most merciful and beneficent, for giving us

enormous opportunity endowing us with enough energy and patience to carry on andcomplete this project work.

We wish to express our profound gratitude and sincere appreciation to our respected

supervisor Ahmed Shiblee Nomanof the Department of Civil Engineering of the World

University of Bangladesh, for his continuous guidance, dynamic supervision, invaluable

suggestion and unfailing enthusiasm throughout the process of completing the project.

His noble guidance and advice in every segment for the preparation and completion of

this work carry a most pleasant experience in the lives of the authors, which imbued with

ever ending remembrance of his great contribution.

We exceptionally express our deepest gratitude and thanks to professor

A.F.M Abdur Rauf, Advisor of the Department of Civil Engineering and

Mr. Skender Ali, Associate Professor of the Department of Civil Engineering,

Mr. Rabindra Ranjan Saha, Head of the Department of Civil Engineering of the World

University of Bangladesh, Dhaka, for their grating necessary permission to conduct this

project work and also for this whole hearted support to give us more enthusiastic in doing

this project work.

We are ever grateful to our friends and parents for their inspiration encouragement andblessings.

RANZU AHMED

Reg: WUB 10/08/23/637

MD. ZAHIRUL HOQUE

Reg: WUB 10/08/23/636

MD. MASUD RANA

Reg: WUB 10/08/23/639

MD. ABDUL BATEN

Reg: WUB 10/08/23/623

MD. ABUL KASHEM

Reg: WUB 10/08/23/635


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ABSTRACT

The purpose of this study is to model and analyze the non planar shear wall assemblies

of shear wall-frame structures. Two nos three dimensional models, for open and

closed section shear wall assemblies, have been developed.

These models are based on conventional wide column analogy, in which a planar

shear wall is replaced by an idealized frame structure consisting of a column and rigid

beams located at floor levels. The rigid diaphragm floor assumption, which is widely

used in the analysis of multi storey building structures, is also taken into consideration.

The connections of the rigid beams are released against torsion in the model proposed

for open section shear walls. For modeling closed section shear walls, in addition to

this the torsional stiffness of the wide columns are adjusted by using a series of

equations.

Several shear wall systems having different shapes of wall-frame and Flat Plate shear

wall assemblies have been analyzed by static lateral load, response spectrum where theproposed methods have been used. The results of these analyses are compared with the

results obtained using common shear wall modeling techniques.


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TABLE OF CONTENTS

ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... V

ABSTRACT. . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . vii

TABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. viii

LIST OF FIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...xiii

CHAPTER 1

1. INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . 1

1.2 Objectives .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . 3

1.3 Scope of the Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . 4

1.4 Analysis of Shear Wall . . . . . . . . . . . . . . . . . . . . . . . . . . .... . . . . . 5

CHAPTER 2

2. Literature Review. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.1 Shear Wall Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 7

2.2 Equivalent Lateral Force Method . . . . . . . . . . . . . . . . . . . . . . . . .. 8

2.3 Method of Analysis of Shear Wall Structures . . . . . . . . . . . . . . . . ..10


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2.3.1 Finite Element Analysis (FEA). . . . . . . . . . . . . . . . .. .. . . . 10

2.3.2 Continuous Connection Method (CCM) . . . . . . . . . . . . . . 11

2.3.3 Equivalent Frame Analysis (EFA) . . . . . . . . . . . . . . . . .. . 12

2.3.4 ETABS non Linear Version 8.5 . . . . . . . . . . . . . . . . . . . ...13

CHAPTER 3

3. Research Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

3.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..14

3.2 Behavior of Symmetric Wall Frame. . . . . . . . . . . . . . . . . . . . . . .. .15

3.3 Computer Analysis by E-TABS. . . . . . . . . . . . . . . . . . . . . . . . . 15

3.4 Manual Calculation. . . . . . . . . . . . . . . . . . . . . . . . .20

3.5 Summery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...27

CHAPTER 4

4. Modeling of Shear Walls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

4.1 Two Dimensional (Planar) Shear Wall Models. . . . . . . . . . . . .... . . 30

4.2 Modeling And Analyzing the Shear Wall Model.. . . . . . . . . . . . . . . 31

4.3 Equivalent Frame Model (Wide Column Analysis) . . . . .. . . . .. . . 33

CHAPTER 5


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FIGURES

1.1 Typical Floor Plan of a Shear Wall - Frame Building Structure .. . . . . . . . .... 2

1.2 Typical Shear Wall Sections .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.1 Shape of Shear Wall . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 7

2.2 Building Structure Subjected to Equivalent Lateral Loads. . . . . . . . . . . . . 9

4.2 Shear Wall Model . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . ..30

4.2.2 ETABS Shear Wall Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

4.2.3 ETABS Model Used for Linear Procedures . . .. . . . . . . . . . . . . . . . . .... . . 32

4.3.1 Equivalent Frame Model of a Shear Wall . . . . . . . . . . . . . . . . . . . . . ....33

5.3 U-Shaped Shaped Shear Wall Assembly . . . . .. . . . . . . . . . . . . . . . .... . .39

5.4 L-Shaped Shaped Shear Wall Assembly . . . . .. . . . . . . . . . . . . . . . . ... . .39

5.5 W-Shaped Shaped Shear Wall Assembly . . . . . . . . . . . . . . . . . . . . . . . 40

5.6 H-Shaped Shaped Shear Wall Assembly . . . . .. . . . . . . . . . . . . . . . . . . . ..40

5.7 T-Shaped Shaped Shear Wall Assembly . . . . .. . . . . . . . . . . . . . . . . . . ...40

5.8 Plan of a Rectangular Wall Assembly . . . . . . . . . . . . . . . . . . . . . . . . . 41


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CHAPTER 1

INTRODUCTION

1.1 Introduction

High rise building is a structure vertically cantilevered from the ground level subjected

to axial loading and lateral forces. It consists of frames, beams, shear walls, core walls,

and a slab structures which interact through there connected edges to distribute lateral

and axial load imposed on the building. Lateral forces generated either due to wind

blowing against the building or due to the inertia forces induced by ground shaking

which tend to crack the building in shear and push it over in bending. These types of

forces can be resisted by the use of shear wall system which is one of the mostefficient methods of ensuring the lateral stability of tall buildings.

For building taller than ten stories, frame action obtained by the interaction of slabs

and columns is not adequate to give the required lateral stiffness. It also has become

and uneconomical solution for tall buildings. However it can be improved by statically

placing shear walls as it is very effective in maintaining the stability of tall buildings

under severe wind or earthquake loading.

1. Structural Frame Systems: The structural system consist of frames.

Floor slabs, beams and columns are the basic elements of the structural

system. Such frames can carry gravity loads while providing adequate

stiffness.

2. Structural Wall Systems: In this type of structures, all the vertical

members are made of structural walls, generally called shear walls.

3. Shear WallFrame Systems (Dual Systems): The system consists of

reinforced concrete frames interacting with reinforced concrete shear

walls.


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Most of the high rise reinforced concrete building structures in Bangladesh have shear

wall-frame systems. A typical floor plan of a shear wall-frame building structure is

given in Figure 1.1.

Figure 1.1 Typical Floor Plan of a Shear Wall-Frame Building Structure


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1.2 OBJECTIVES:

The main objectives of the research are as follows:

1. To carry out a frame analysis on shear wall models using ETABS non

linear version 8.5 software.

2. To check the reliability of frame analysis method compare to wall

frame shear wall and flat plate shear wall.

3. To determine the ultimate lateral load due to wind and earthquake.

4. To find out and compare the different calculated value of those wall

frame and flat plate shear wall structures.


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1.3SCOPE OF THE STUDY

The main intention of the research work presented in this thesis is to study typical high

rise building structures with shear wall-frame systems. Proper analysis and design of

building structures that are subjected to static and dynamic loads is very important.

Another important factor in the analysis of these systems is obtaining acceptable

accuracy in the results. The object of this study is to model and analyze shear wall-

frame structures having non-planar shear walls. In order to reduce the required time

and capacity for the analysis of the structural systems, frame elements are used instead

of plane stress elements in modeling the shear walls. Two two-dimensional shear wall

models, based on the conventional wide column analogy, are developed for modeling

(a) open and (b) closed section non-planar shear walls. The proposed models can be

used in both static and dynamic elastic analysis of shear wall-frame structures.

The accuracy and the efficiency of the proposed models are tested by performing static

lateral load analysis, response spectrum analysis and time history analysis on single

shear walls and shear wall-frame systems. In order to check the validity of the

proposed models, the same analysis are performed on the considered structural

systems, in which shear walls are modelled by wall elements of ETABS [8.5]. In

addition, comparisons are made with several methods and experimental results from

the literature.

In the first part of the static lateral load analyses, single shear walls having different

cross- sections are taken into consideration. They are subjected to point loads acting at

floor levels. Two different loading conditions are applied on the structure:

(a) Axisymmetric lateral loading

(b) Pure floor torsions

Translations and rotations at floor levels are obtained for different shear wall models.


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1.4 Analysis of shear wall:

It is a fact that shear walls have high lateral resistance. In a shear wall-frame system,

this advantage can be used by placing shear walls at convenient locations in the plan

of the building.

In general, shear walls are in planar form in the plan of the building. However, some

combinations of planar walls are also used in the structural systems. Typical non-

planar shear wall sections used in the building structures are given in Figure 1.2

Figure 1.2 Typical Shear Wall Sections


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The analysis of shear wall-frame structures is more complicated than frame systems.

In order to reflect the actual behavior of the shear walls, several models have been

developed. Wide column analogy, braced frame analogy and shell element derived by

using finite element formulation are the most popular models. In the first two models,

frame elements are used and in the last model, plane stress elements are used.

Another important point for the lateral load analysis of building structures is modeling

the structural system. A common method which is widely used in design offices is to

perform analysis on a two dimensional model obtained from the actual three

dimensional system by using some simplifying assumptions. The total number of

degrees of freedom is reduced significantly through this method. Some computer

programs which model the buildings in series of two dimensional frames in two

orthogonal directions use the same logic. The displacement compatibility is

established by infinitely rigid slabs at floor levels.


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CHAPTER 2

Literature review

2.1 Shear walls systems

Shear walls have been the most common lateral force resisting elements for tall

building besides frame system. It is an efficient method of ensuring the lateral stability

of tall buildings and also efficient against torsional effects when combined together

with frame structure. There stiffness is such that sway movement under wind &

earthquake load can be minimized.

Structural forms of shear wall are commonly using buildings of 10 to 30 stories.

Monolithic shear wall can be classified as short, squat or cantilever as in fig 2.1

according to there height/depth ratio. The walls may be planer, flanged or core in

shape.

Figure : 2.1 Shapes of Shear Wall


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2.2. Equivalent Lateral Force Method

The equivalent lateral force method is commonly preferred by design engineers

because of its simplicity. It is based on the following assumptions:

1. The effects of yielding on the building structure are approximated

using elastic spectral acceleration reduced by a modification factor.

2. A linear lateral force distribution can be used to represent the

dynamic response of the building structure.

The following procedure is used for the analysis of building structures using the

equivalent lateral load method:

1. Determination of the first natural vibration period.

2. Determination of the total equivalent seismic load.

3. Determination of design seismic loads acting at storey levels.

4. Determination of points of application of design seismic loads.

5. Analysis of the structural system.

A building structure subjected to lateral forces obtained by the equivalent lateral forcemethod is shown in Figure 2.2. A triangular distribution of equivalent lateral loads

with zero loading at the base of the structure is considered in the analysis.


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Figure 2.2 Building Structure Subjected to Equivalent Lateral Loads


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2.3 Method of Analysis of Shear wall structures

Analysis on shear wall structures can be made in elastic, elastic-plastic and ultimate

condition. Due to its simplicity, elastic analysis is still widely in used today in the

design offices.

There are several methods available for the analysis of coupled shear wall as been

introduced in Chapter 1. Three common basic methods that usually been used are

finite element analysis, continuous connection method and equivalent frame analysis.

2.3.1 Finite Element Analysis (FEA)

In finite element method, the main idea is to discrete a complex region defining a

continuum into simple geometric shapes called finite element. The material properties

and the governing relationships are considered over these elements and expressed in

terms of unknown values at element corners. An assembly process, duly considering

the loading and constrain, results in a set of equations. Solution of this equations gives

us the approximate behavior continuum.

The advantage of finite element analysis includes in which the nonlinearities behavior

of material or structure can be considered in the analysis. The term non linear is use in

structural analysis to describe a solution where the deformation is not proportional to

the applied load. This is may be due to geometric nonlinearities, materials

nonlinearities and the contact of bodies with geometric and materials nonlinearities. It

also virtually may include various geometrical shapes of structures.


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Factors that usually considered for nonlinear concrete materials model used in the

analysis are includes of.

1) Nonlinear behavior in compression at materials including hardeningand softening

2) Fracture of concrete in tension based on nonlinear fracture mechanics3) Biaxial strength failure criterion4) Reduction of the shear stiffness after cracking

Nonlinear finite element analysis (NLFEA) make possible for me to analyze models

real life conditions on the desktop. The analysis can be made in elastic, elasto-plastic

and ultimate conditions. Results obtain cold offer very good alternatives to

excremental results. This method is cheaper but time consuming whereas relatively

simple force distribution output is required for design but certainly not true for

research purposes.

2.3.2 Continuous connection method (CCM):

Continuous connection method is an analysis where the coupling beams of shear wall

structure are replaced by continuous connected media along its height. The coupling

beams are assumed to deform with a point of contra flexure, normally at mid-span.

The walls are assumed as cantilever system on a rigid foundation and it neglects the

effect of the beams axial deformation. The openings are replaced by a single

continuous shear medium.

The method also allows simple elevation for any load pattern to be included in the

analysis. A simple analytical solution can be derived, including the accuracy of force

and deflection by explicit mathematical relationships which are dependent of the no.

of stories. The analysis can be made in elastic and elasto-plastic conditions. Elasto-

plastic method of analysis based on CCM is done by dividing the structure into elastic

and plastic zone.

Several problems may arise when obtaining the solution to the equation if unusual

base forms, irregularities of openings, such that new boundary conditions that has to

be applied to the equation.


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2.3.3 Equivalent Frame Analysis (EFA)

Frame analysis may also be called wide frame analogy . It is a simple method and can

be used in plan frame programs. This method treats the walls and beams as discrete

frame members .walls and connecting beams are replaced by the line element of

stiffness equal to those of the units they replaced.

The method of analysis is based on the assumption that a linear relationship exists

between the applied action and the resulting displacement .This assumption requires,

first the material of the frame shall behave in Hookean manner at all points and

throughout the range of loading considered. Second, it assumes that the changes in the

geometry of the structure are small enough to be neglected when the internal action

are calculated .

Two basic procedures in frame analysis are flexibility method and deflection or

stiffness method. in the first approach, certain action are temporarily removed, these

action are the unknowns in the compatibility equations which lead to the

complementary solution. In the second approach. certain displacements are prevented

or removed. The equilibrium equations are written in terms of these unknown to be

sought displacements.

Stiffness method is the basic method used nonlinear ETABS-8.5 to analyse structures.

It can be performed in a linear analysis or geometrical nonlinear analysis. However,

this second order elastic analysis has not yet included in the version ETABS 8.5 non

linear. Since this study was using non linear version ETABS 8.5.

So the shear wall models where actually analyzed using first-order elastic analysis of

stiffness method. In this method, the structures assumed to behaves linearly elastic so

that the principles of superposition applied.

Occasionally these method give the wrong impression on the behavior of shear wall

structure under loading (Kwan 1993), however due uncertain and inability to

understand the post-elastic behavior, time constraint and also its simplicity, the results


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output are still acceptable by engineers. Thus this study was carried out to view the

reliability of the method compared to the analytical and NLFEA method.

2.3.4 ETABS non linear version 8.5

This manual presents a set of simple building systems that have been analyzed using

ETABS Version 8.5. The examples demonstrate some of the analytical capabilities of

the ETABS system. For purposes of verification, key results produced by ETABS are

compared to independent sources, such as hand calculated results, theoretical or

published results, or results obtained from other structural/finite element programs that

are verified not using ETABS. The examples cover each type of element, static and

dynamic analysis and linear and nonlinear options.

For each example, this manual contains a short description of the problem; a list of

significant ETABS options activated; and a comparison of key results with theoretical

results or results from other computer programs.

Significant Options of ETABS Activated

Two-dimensional frame analysis

Vertical beam span loading

No rigid joint offsets on beams and column

Column pinned end connections


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CHAPTER 3

RESEARCH METHODOLOGY

3.1 Introduction:

The Research Methodology was started with problem identification on reinforced

concrete shear wall and setting up the objectives & scope of study. Then all the related

background information were collected an studied for the literature review for

knowledge updating.

The major parts of this study are structural modeling and computational analysis using

frame analysis method in non linear version ETABS. The results obtain then being

assessed, interpreted and compared with one which was obtained from the calculation.

3.2: Behavior Of Symmetric Wall-Frame

Considering the separate horizontal stiffnesss at the top of a typical 10-story elevator

core and a typical rigid frame of the same height the core might be 10 or more times as

stiff as the frame. If the same core and frame were extended to a height of 20 stories, the

core would then be only approximately three times as stiff as the frame. At 50 stories the

core would have reduced to being collects half as stiff as the frames. This change in therelative top stiffness with the total height occurs because the top flexibility of the core,

which behaves as a flexural cantilever, is proportional to the cube of the height ,where as

the flexibility of the frame ,which behaves as a shear lever, is directly proportional to its

height. Consequently, height is a major factor in determining the influence of the frame

on the lateral stiffness of the wall-frame.

A further understanding of frame interaction between the wall and the frame in a wall-

frame structure is given by the deflected shapes of a shear and a rigid frame subjected

separately to horizontal loading. The wall deflects in a flexural mode with concavity

downwind and a maximum slopes at the top, while the frame deflect in a shear mode

with concavity upwind and a maximum slope at the base. When the wall frame are

connected together by pin-ended links and subjected to horizontal loading, the deflected

shape of the composite structure has a flexural profile in the lower part and a shear profile

in the upper part. Axial forces in the connecting links cause the wall to restrain the frame

near the base and the frames to restrain the wall at the top. Illustrations of the effect of


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wall frame inter action are given by the curves for deflection, moments and shear for a

typical wall-frame structure. The deflection curve and the wall moment curve indicate the

reversal in curvature with appoint of inflexion ,above which the wall moment is opposite

in sense to that in a free cantilever. The share as approximately uniform over the height

of the frame, except near the base where it reduces to a negligible amount. at the top,where the external share is zero, the frame is subjected to a significant positive shear

,which is balanced by an equal negative share at the top of the wall, with a corresponding

concentrated interaction force action between the frame and the wall. Special

consideration may have to be given in the design to transferring this interaction force

3.3 Computer Analysis:

i. GRID ->X-DIC-> 6, Y-DIC-> 5UNITK-FTNO OF story-2

Typical story height=10

Bottom story height=6

Custom Grid spacing -> Edit Grid->

X Grid Data->

A=0,B=15,C=20,D=30,E=55,F=60

Y Grid Data->

1=0,2=25,3=45,4=50,5=60

ok-> Grid only-> ok->Get Plan

ii. Define-> Materials properties->Concrete->Modify/Show Materials-> Materials Name-Concrete->

iii. Define -> Frame Section-> Delete all Properties->Add/Wide Flange -> Add rectangular->

Section Name-> [For Beam b 10 X 18 Similarly

Selection C 18 X 21, GB 10 X 18

Materials->Conc-> Depth 18, Width->10->

Reinforcement-> Beam-> Concrete Cover to Rebar center->2.5(Top)-

>2.5(Bottom)-> ok->

Ok


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Properties:

Type of Property to find

B1=10 X 18

B2=10 X 21

B3=10 X 24

C1=18 X 21

C2=18 X 24

C3=21 X 24

GB=10 X 18->ok->ok->

Define-> wall/slab/Deck section-> Slab 1->

Add new Slab->7 ->Concrete->

Membrane-7

Bending-7

Plate->ok->

Add New Slab->5->concrete->

Membrane->5

Bending->5

Plate->ok->Add New Slab->4->concrete->

Membrane->4

Bending->4

Plate->ok->(Draw lines)->1

Properties of Object

Property [say B1 10 X 18(Draw lines at Plan)

(at story Level -2)[one story]

[Similarly B1,B3 Beam line draw at plan]

All stories-> Select -> Properties->C1 18 X 21

C2 18 X 24, C3 21 X 24 all Column input on plan->

Select one story new select (plan)-> Base->ok->Esc->

Select all column->(select)-> Fixed Support(select)->ok->

Again (Draw lines )(For GB)-> Property-> Select->

One story->Plan->Story-1->ok->

GB 10 X 18,(Now Draw GB lines at plan)

(Esc)->

Plan-> story-2->ok->

Select->Property->4->Draw at Plan

Property->5->(Draw at plan)

Again property & select ->7-> & Draw at Plan


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Select-> All Panel (all) and select object fill->Apply all windows ->ok->

UNIT-KFT->

Edit-> Edit Story data-> insert story->

Story height-10

No of stories->6story

Select-> (all)->Assign-> Shell area loads-> Uniform->Dead->unit(lb-ft)->

load 120 lb ft->ok->

Select (P5 )->Assign-> shell/area loads-> Uniform->

Live-> Unit(lb ft)->Load-40 lb ft ->ok->

Define ->static load case->

Load TYPE Self WT Multiplier Auto Lateral Load

EQX QUAKE 0 UBC-94->add New

load->

EQY QUAKE 0 UBC-94->add Now

load->WIND X WIND 0 UBC-94->add Now

load->

WIND Y WIND 0 UBC-94->add Now

load->

Select->EQX,- QUAKE- 0- UBC - 94

Modify lateral load ->X-Dic->Method a->

Ct(ft)->0.03->Rw->12

Seismic Co-Efficient-> Seismic Zone factor, z

Per Code 0.20->Site Co-Efficient->1.2/1.5Importance factor =I=1.0

Y-Dic->Method A->

Ct(ft)->0.03->Rw=12

Seismic zone Factor,2

Per Code->0.20->

Site Co-Efficient, s=1.2

Importance factor I=1.00->ok->ok->

Select [all Stories]->

(All)->Assign->Shall/Area->

Area object Mesh options->

[Area object auto Mesh options]

Auto mesh object into structural elements

Further Sub divide auto mesh with Maximum elements size of 4->ok-.

Select auto area mesh ->

Apply all windows->

Ok->

Select (all)->D1 ->ok->


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Define->Mass source-> From loads->

Dead-1.2 Add->

Live-1.6 add->

EQX-> 1 Add->

EQY-> 1 Add->

WINDX=1 Add->ok->

WINDY=1

Define->Special Seismic Data->

Do not include special seismic design data->

Ok->

Analyze->select analysis option->

(OFF) Dynamic analysis->

Include P-Data->Select P-Data

Parameters->

Maximum Iteration10Dead-12 Add->

Live-1.5 Add->ok

Analyze->Run Analysis->Save->

Options->Preferences->Concrete Frame

Design-> Design Code->ACI 318-99->ok->

Design-> Concrete Frame Design->

Start design/Check of Structure Again left site select ->Design->concrete frame

Design

Start design/Check of Structure

Plan->Top of building->ok->Display->Show Deformed shape->

Dead Static Load ->EQX, EQY, WINDX, WINDY etc 14/16 Loads ->ok->

Now plan corner select, so we found slab panel any corner deflection value

() select -> Dcon 14 (similarly we found any type of deflection)

Display->Show member force/Stress diagram->

Frame/pier/spandrel force->

Dead static load moment 3-3

Similarly share 2-2

Option ->Moment diagram on tension side ->

Beam deflection calculation->

Select any Beam member then right button click we get deflection

value/moment/share


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Rebar calculation:

Design-> Concrete frame design->

Display design info .->

Design output->

Longitudinal Reinforcements->ok->

Share Reinforcements

Rebar percentage

The approximate method of analysis is valuable in providing an understanding of a wall-

frames behavior and in allowing the initial sizing of members as part of the preliminary

design process. It does not allow, however, for changes of properties within the height of

the structure or for the effects of axial deformations of the columns that in a tall slender

frame could be significant. Therefore, a computer analysis, using one of the widely

available structural analysis programs, should be used for the final design.

Modeling the wall frame structure for a computer analysis will follow the principles

outlined in chapter 4. If the structure is symmetric on plan and subjected to symmetric

loading. So that it does not twist, a planer model of only one-half of the structure

subjected to one-half of the loading need be considered. Shear walls and share wall

core are represented by simple column cantilevers with corresponding moments of

inertia, while the frames are represented by equivalent assemblies of beam elements.

In the planar model the cantilever columns and frames are constrained at each floor by

the analysis programs nodal constraint option, if available, or connected by axially

rigid links, to cause equal horizontal displacements of the bents, as imposed on the

structure by the in plane rigidity of the floor slabs. The horizontal loads may be

applied to the nodes of any convenient column or frame.


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Analysis of Shear will due to lateral load.

3.4 : Manual Calculation

Worked Example:

15 story Building, 52.5m height, wall frame structure.

Frame Type Interior Column

Ixx (m4)

Exterior Column

Iyy (m4)

Girder

Type-01 0.052 0.030 0.007 (15"24")

Type-02 0.030 0.013 0.005 (12"24")

Core Inertia = 597.75 m4

Elastic modulus. E = 2.0107kn/m

2

Wind pressure = 1.5 kn/m2

Step-01

Determine parameter- = H

(a) Add the flexural rigidities EI of all walls and cores to give the total (EI)t. In this

case there is only a core.

For the core I = 597.75 m4.

There fore (EI)t= 2.0107597.75

= 11.95 109kn-m

2

(b) Evaluate the when rigidities (GA) of the rigid frame bents and any wall frame

bents, using equation 11.26, 11.27 and 11.28 and sum them to give the total (GA)t. In this

case there are only the former.

The when rigidities (GA) of the two types of frame (1) and (2) by using the

expression. For frame type - 01


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Now, GA =

CG

h

E

11

12

=

5.3

052.0303.02

1

62.7

007.04

15.3

100.212 7

= 20.1614.2725.3

100.212

= 2.38 105Kn

FOR FRAME TUPE-02

GA =

5.3

03.03013.02

1

62.7

005.04

15.3

100.212 7

= 17.303815.3

10212

7

= 1.67105Kn

Total (GA)t= GA = (22.38+21.67) 105

= 8.10105Kn

(c) Use the Values obtained in items a and b to evaluate H, using

t

t

EI

GAHH

= 52.591095.11

1010.8

Therefore 43.0H


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An analysis for uniformly distributed loading in then made as follows.

Step-02:

Determine Horizontal Displacements:

The displacement at height z from the base is obtained by substituting H and

Z/H in equation (11.10) or, at ternotively by taking the value of K1corresponding of the

obtained values of H and Z/H from fig 1.2 and substituting it in the expression.

30.11/8

11

4

HZHKEI

wHZY

t

For the given structure, the wind loading per unit height.

W= 1.545.73 = 68.60 Kn/m

At the top = H = 0.4

Z/H = 1, K1=0.87 0.43 0.87

0 1.0

87.01095.118

5.5260.689

4

HY

= 0.0047 m.

STEP-03

Determine maximum story drift Index:

The maximum story drift index is obtained by referring to fig 2.2 and scaning

the appropriate H curve to find the maximum value of K2, which is then substituted in

max6

max 2

3

kEI

WH

dz

dy

t

For the given structure, K2(max) = 0.36

Therefore, the maximum story drift index approximate height is obtained as,

Z/H= 0.55m

36.01095.116

5.5260.68max

9

3

dz

dy

= 0.000050 2 0.2


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0.43 0.36

0 0.41

STEP-04

Determine bending moments in the wall and frame.

(a) The total moment carried by the walls in obtained either by substituting H and

Z/H is equation (11.16) on by taking the appropriate value of K3from fig 3.2 and

substituting in

Mb(Z) = 3

2

2K

WH

For example, at the mid 6th story level Z = 22.75 m, Z/H = 22.75/02.5 = 0.43 of

the structure considered, K3= 0.283.

Therefore, the moment in the core is obtained is,

Mb= 283.02

5.526.68 2

= 2.67104Knm H 2 0.05

0.43 2.28 (K3)

0 0.35

For a structure consisting of multiple walls, the moment in any individual wall is

then obtained by distributing the total wall moment between the walls in proportion to

their flexural rigidities.

(b) The total moment in the set of frames of a level Z from the base as expressed inequation (11.17) is equal to the difference between the total external moment and the

total moment in the walls of that level.

Ms(Z) =

)(2

2

ZMZHW

b


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At the same mid-sixth story level of the given structure as in item 4a. The moment

carried by the frames is obtained as.

Ms= 4

2

1067.22

75.225.526.68

= 3.65103Knm

The moment in the individual frames is obtained by distributing the total frame

moment between the frames in proportion to their shearing rigidities.

Therefore, the moment in frame type-01

= 35

5

1065.31010.8

1038.2

= 1.07103 Knm

and the moment in frame type-2

= 35

5

1065.31010.8

1067.1

= 752.53 Kn-m.

The banding moments of other levels of the structure have been found similarly

and are potted in fig 11.10 (b)

STEP-05

Determine shear forces in wall and frame =

(a) The total shear in the walls at a level Z from the base may be obtained by

substituting H and Z/H in equation (11.19) on by taking the value of K4from fig 4.2

and substituting in equation (11.33)

Qb(Z) = WHK4

For example, at the mid-seventh story level (Z=26.25m, Z/H = 0.5 of the structure

considered, K4= 0.22.


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Therefore, the their in the core is obtained as,

Qb= 68.605250.22 H 2 0.02

= 792.33 Kn 0.43 0.22

0 0.28

K4= 0.22

For a structure consisting of multiple walls, the shear force in the individual, walls

is then obtained by distributing the total shear between the walls in proportion to their

flexural rigidities.

(b) The total shear in the frames of a height Z is the difference between the external

shear and the total wall shear of that level, as determined above.

Qs(Z) = W (H-Z) - Qb(Z)

At the same mid seventh story level of the given structure, as in item 5a, the shear

carried by the frames is obtained as

Qs= 68.6 (52.5-26.25) - 792.33

= 1008.42 Kn.

The shear in the individual frames is given by distributing the total frame shear

between the frames in proportion to their shearing rigidities.

Therefore, the shear in frame type-01

= Kn30.29642.10081010.81038.2 5

5

And the shear in frame type-2

= 42.10081010.8

1067.15

5

= 208 Kn


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The values of share at other levels of the structure have been found similarly and

are potted in fig 11.10.


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Summary:

The horizontal interaction between the walls and frames in wall-frame structure causes

an increased lateral; stiffness of structure, reduced moments in the walls, and, in a

uniform structure, an approximately uniform shear in the frame. The benefits of

interaction increase with-frames are economical for buildings of to 15 stories or more.

The wall-frame horizontal interaction occurs because the different free-deflected

shapes of the wall and the frame are made to conform to the same configuration by the

axially stiff connecting girders and slabs.

An approximate theory is presented for non twisting uniform wall-frames on the basis

of a continuum model of the structure, with a flexural cantilever representing the

walls, a shear cantilever representing the frames, and a horizontally stiff continuous

linking medium repressing the slabs and girders. A characteristics differential equation

for deflection is retrain in terms of the two structural parameters of the wall frames.

This has be solved for three tropical types of loading to obtain general formulas for the

deflections, the story drift, the shears, and moments on the walls and frames. Design

curves are also develop that allow repeat estimates of the deflections and forces. The

solution by both formulas and grapes give close estimate of the deflection and forces

in non twisting uniform wall frames of 15 stories or more, and approximate estimate

of the forces in non-twisting, non-uniforms wall frames, which may be use as guide

lines for preliminary design. An accurate estimate of the deflections and forces in non-

uniform or in twisting wall frame structures requires a computer analysis.


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CHAPTER 4

MODELING OF SHEAR WALLS

According to Earthquake Code a shear wall is defined as a vertical structural member

having a length of seven or more times greater than its thickness. Being the major

lateral load resistant units in multi storey building structures, shear walls have been

studied experimentally and theoretically over the last fifty years.

In the lateral load analysis of building structures having shear walls, proper methods

should be used for modeling planar and non-planar shear wall assemblies. Shear wall

models in the literature can be divided into two:

1. Models developed for elastic analysis of building structures.

2. Models developed for nonlinear analysis of building structures.

The investigation of nonlinear shear wall models is beyond the scope of this study.

In this chapter, shear wall models developed for the lateral load analysis of multi

storey structures in elastic region are presented. Since the methods for modeling

building structures are analyzed separately (two dimensional modeling and three

dimensional modeling are presented in Chapter 2) shear wall modeling studies can

also be investigated in according to the two and three dimensional approaches.

4.1 Two Dimensional (Planar) Shear Wall Models

The literature mentions several shear wall models that were developed for two

dimensional elastic analysis of multi storey building structures. In this part, a review

of these models is given.


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4.2 Modeling and Analyzing the Shear Wall Model:

Generally there are several steps in modeling and analyzing the shear walls. First is by

installing the section properties for every part of the shear wall using section maker in

ETABS. Followed by building the frame models for every shear walls in ETABS 8.5

and all the section properties and restraints are assigned to the respective part of the

structure. Then applying the structure with load and analyzed it too obtain all the

results.

Figure 4.2 :Shear Wall Model


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4.3 Equivalent Frame Model (Wide Column Analogy)

The equivalent frame model was developed the analysis of plane coupled shear wall

structures. The model was limited to lateral load analysis of rectangular building

frames without torsion. It was improved in the 1970s by Mcleod and McLeod and

Hosny for the analysis of nonplanar shear walls. In the equivalent frame method,

which is also known as wide column analogy, each shear wall is replaced by an

idealized frame structure consisting of a column and rigid beams located at floor

levels. The column is placed at the walls centroidal axis and assigned to have the

walls inertia and axial area. The rigid beams that join the column to the connecting

beams are located at each framing level. In this method, the axial area and inertia

values of rigid arms are assigned very large values compared to other frame elements.

Due to its simplicity, the equivalent frame method is especially popular in design

offices for the analysis of multistory shear wall-frame structures.

Figure 4.3.1 Equivalent Frame Model of a Shear Wall


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CHAPTER 5

THREE DIMENSIONAL MODELING OF SHEAR WALLS

IN THE LATERAL LOAD ANALYSIS OF SHEAR

WALL-FRAME STRUCTURES

5. Three Dimensional Modeling of Shear Walls in the Lateral Load Analysis of

Shear Wall-Frame Structures

As stated in Chapter 1, the main objective of this study is to model nonplanar shear

wall assemblies in a realistic and feasible way for the analysis of shear wallframe

structures. The modeling studies are based on rigid diaphragm floor assumption and

the three dimensional equivalent frame method, in which a planar shear wall is

modeled using an equivalent column and rigid beams at floor levels. A generalized

three dimensional finite element program, ETABS 8.5, is used in the studies.

In the first part of this chapter, the basic assumptions used in the modeling studies are

presented. These assumptions are divided into three categories:

1. Material behavior

2. Element behavior

3. Structural behavior

In the second part, the models developed for nonplanar shear walls having open and

closed sections are presented. The comparison of the proposed models with the other

shear wall modeling methods (using ETABS wall element and conventionalequivalent frame method) in lateral load analyses are made in the last part of the

chapter.


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5.1 Basic Assumptions

In the analysis of all kinds of structures, a number of assumptions should be made in

order to reduce the size of the actual problem. As stated above, these assumptions can

be divided into three categories: material behavior, element behavior and structural

behavior. In this part, the assumptions used in the modeling studies are presented.

5.1.1 Material Behavior

The behavior of the materials in this study is assumed to be linear elastic. Linear

elasticity is the most common material model for analyzing structural systems and is

based on the following assumptions:

1. The material is homogenous and continuous.

2. The strain increases in a linear portion as stress increases.

3. As stress decreases, the strain decreases in the same linear portion.

4. The strain induced at right angles to an applied strain is linearly

proportional to the applied strain, which is called Poissons ratio

effect.

In addition, the effects of cracking, creep, shrinkage and temperature on the material

are not taken into consideration.

5.1.2 Element Behavior

Two different structural elements are used in the analyses. The three dimensional

frame element, which is presented in Chapter 2 (Figure 2.4), is used for modeling the

beams and columns of the structural systems. It is assumed to have six degrees of

freedom at each end. The elements of the equivalent frame model (equivalent wide

column and rigid beams) are also modelled using three dimensional frame element.


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The three dimensional shell element, which is used for modeling shear walls in

verification studies, is assumed to have six degrees of freedom at each node.

Additional assumptions about the element behavior are as follows:

1. Shear deformations in the structural elements are ignored.

2. Frame elements and shell elements have uniform cross-sections

throughout the length.

5.1.3 Structural Behavior

The multistory building systems analyzed in this study are considered to be rigid

frame structures. In such systems, all structural elements of the system are assumed to

have infinitely rigid moment resistant connections at both ends. Another assumption

about the structural system is the linear elastic structural system behavior, in which the

deformations are proportional to the loads. It is widely used in structural analysis and

leads to a very important simplification called superposition.

In superposition, if a linear elastic structure is subjected to a number of simultaneously

applied loads, the overall response can be determined by summing the responses of the

structure to the loads applied at one time. Based on this assumption, the behavior of

the structural system under eccentric lateral loads can be determined by superposing

the behavior under the considered lateral loads, which are applied axisymmetrically,

and the behavior under the pure torsion produced by these eccentric lateral loads.

In the analysis performed in this study, it is assumed that only the structural

components participate in the overall behavior. The effects of structural components,

such as non-structural walls, are assumed to be negligible in the lateral load analysis.

One of the most important assumptions in this study is the rigid diaphragm floor

assumption, a common assumption which simplifies the problem significantly and

reduces computing time. The rigid diaphragm floor assumption is based on the rigidity

of the floors in their own plane. Field measurements on a large number of building

structures verified that in-plane deformations in the floor systems are small compared

to the inter-storey horizontal displacements. With the use of rigid floor diaphragms,

the horizontal lateral loads acting at the floor levels of a building structure are directly


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transferred to the vertical structural elements (columns and shear walls). This results in

three displacement degrees of freedom at each floor level (translations in two

orthogonal directions and rotation about vertical direction), and in-plane

displacements of the diaphragm can be expressed in terms of these displacements .

In dynamic analyses, it is assumed that the mass of each floor is lumped at a single

node on the floor, which is generally the master node. The mass, m, is defined only in

three degrees of freedom due to the constraining effect of the floor diaphragms. This

approach is suggested by Chopra .

5.2 Modeling Nonplanar Shear Walls

Due to deficiencies in the two dimensional and the pseudo three dimensional lateral

load analyses that are discussed in Chapter 2, three dimensional analysis should be

performed for shear wall-frame structures having nonplanar shear wall assemblies. In

this study, the modeling of nonplanar shear walls is examined in two parts, are as

follows:

1. Open sections

2. Closed sections

Two different modeling methods are developed for open and closed section shear wall

assemblies. These methods are based on the behavior of the assemblies in shear wall-

frame structures subjected to lateral loads for which the rigid diaphragm floor

assumption is valid. In the modeling studies, the conventional equivalent frame model

is used with significant modifications. The translational and rotational response of the

shear wall assemblies are considered separately and the actual behavior of the

structure subjected to eccentric lateral loads is assumed to be obtained by the

superposition of the two responses. In the modeling and verification studies, SAP2000

software is

used. However, the proposed models can be implemented in any three dimensional

frame analysis program having constraint option.

In the following two parts, the proposed models developed for open and closed section

shear wall assemblies are presented. In the last part, the performance of these models


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is investigated by comparing the responses of the assemblies in static and dynamic

loading.

5.2.1 Modeling of Open Section Shear Walls

It is a common assumption that due to the high in-plane stiffness of floor slabs, open

section shear walls can be considered as thin-walled beams of non-deformable contour

. In modeling open section shear walls, each planar wall in the assembly is replaced

with a column having the same mechanical properties of the wall as in the equivalent

frame method. In order to ensure the vertical compatibility of the displacements, the

rigid beams at floor levels are rigidly connected to each other at the corners. In

addition, the ends of the rigid beams that are connected to each other are released

(disconnected) from the connection joint only for torsional moments. In another

words, the transfer of torsional moments between rigid beams is prevented. In Figure

the connection details of two orthogonal shear walls are given.

In three dimensional analysis of open shear wall assemblies modelled by the

conventional equivalent frame model, serious errors occur especially in the analysis of

assemblies subjected to torsion. The stiffness of the structural system becomes stiffer

than with finite element modeling. In the studies, it is observed that releasing the ends

of the rigid beams from the connection joint decreases the torsional stiffness of the

shear wall assembly significantly. This difference can be seen in the comparison

studies of open section shear walls presented in the last part.

Several modeling studies are performed on the open section shear wall assemblies.

The plans of the analyzed open section shear walls and the corresponding models

developed by the proposed method are given in Figure 5.3 to 5.7.


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Figure 5.3 U-Shaped Shear Wall Assembly

Figure 5.4 L-Shaped Shear Wall Assembly


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Figure 5.5 W-Shaped Shear Wall Assembly

Figure 5.6 H-Shaped Shear Wall Assembly

Figure 5.7 T-Shaped Shear Wall Assembly


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5.2.2 Modeling of Closed Section Shear Walls

The proposed model for closed section shear wall assemblies is similar to the model

developed for open section shear wall assemblies. The columns are placed at the

walls centroidal axes and assigned to have the same mechanical properties of the

walls. Rigid beams are located at the floor levels and make rigid connections with

each other. Similar to the previous model, the ends of the rigid beams are released at

the connections only for torsional moments.

In the case of pure torsion, due to the rigid floor assumption, it is observed that rigid

beams behave independently from the wide columns and make closed loops at floor

levels. For this reason, the torsional stiffness of the model becomes much smaller than

the torsional stiffness of the actual closed section assembly, as it is a summation of the

torsional stiffnesses of disconnected wide columns in the model. This problem is also

stated by Smith and Girgis . They reported that the closed section shear walls

modelled by the equivalent frame method become less stiff than with the finite

element method.

The proposed model solves this problem by modifying the torsional constants of the

wide columns by using the torsional constant of the shear wall section considered. The

procedure has three steps:

1. Calculation of the torsional constant of the closed section (Jc)

2. Calculation of the torsional constants of the wide columns (Ji)

Figure 5.8 Rectangular Shear Wall Assembly


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5.2.3 Comparison of the Proposed Models With Other Models

The performance of the proposed models are compared with the following shear wall

modeling methods:

1. Modeling with ETABS wall elements

2. Conventional equivalent frame method

In the comparisons, the following single shear wall assemblies are taken into

consideration:

1. U-shaped shear wall (SWS1) shown in Figure 5.3

2. L-shaped shear wall (SWS2) shown in Figure 5.4

3. W-shaped shear wall (SWS3) shown in Figure 5.5

4. H-shaped shear wall (SWS4) shown in Figure 5.6

5. T-shaped shear wall (SWS5) shown in Figure 5.7

6. Rectangular shear wall (SWS7) shown in Figure 5.8

All assemblies have four stories with rigid diaphragms at the floor levels. The height

of all stories is 3.0 m and the thickness of the shear walls is 0.25 m. Other dimensions

of the shear wall assemblies are given in the related figures.

Two different types of analyses are performed in comparison studies of single shear

wall assemblies:

1. Static lateral load analysis.

2. Dynamic analysis to obtain natural vibration periods of the assemblies.

In the static lateral load analyses, two different loading conditions are used as shown.

In loading condition 1, the shear wall assemblies are subjected to axisymmetric lateral

loads acting at floor levels. Each of the four loads is 100 t. In load condition 2,

assemblies are subjected to pure torsions (out of plane moments) at the floor levels.


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CHAPTER 6

Analysis and Result Interpretation:

This Chapter consists of the results from frame analysis. The analysis was carried out

to study the structural behavior of reinforced concrete shear wall structures under

lateral loading at the ultimate condition. The study is focused on the determination of

the ultimate lateral load due to wind and earthquake.

6.1 : Calculation:

SHEAR WALL -1(at point 4, 39, 50)

A. Base Moment: WIND-X

1. Plate Element : MY = 6028 (kip-in)2. Column Element : MY = 6018 (kip-in)

B. Base Moment: WIND-Y

1. Plate Element : MX = 5441 (kip-in)2. Column Element : MX = 5612 (kip-in)

C. Base Moment: EQ-X


D. Base Moment: EQ-Y



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Note:

WIND-X = Wind Load at X-Axis

WIND-Y = Wind Load at Y-Axis

EQ-X = Earth Quake Load at X-Axis

EQ-Y = Earth Quake Load at Y-Axis


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PLATE ELEMENTS

Story Point Load FX (Kip) FY (Kip) FZ (Kip) MX (Kip-in) MY (Kip-in) MZ (Kip-in)

BASE 4 WIND-X -0.29 0 6 0 0 0

BASE 39 WIND-X -0.03 -0.01 2.39 0 0 0

BASE 50 WIND-X 0.29 -0.73 5.98 0 0 0

Summation Base WIND-X -0.03 -0.74 14.36 5641 -6028 -288

COLUMN ELEMENTS


BASE 4 WIND-X -0.26 0 5.93 0 0 0

BASE 39 WIND-X -0.03 -0.01 2.1 0 0 0

BASE 50 WIND-X 0.31 -0.71 6.76 0 0 0

Summation Base WIND-X 0.02 -0.72 14.79 5612 -6018 -288


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PLATE ELEMENTS


BASE 4 EQ-Y 0.05 -0.2 36.8 0 0 0

BASE 39 EQ-Y 0 -0.09 -13.61 0 0 0

BASE 50 EQ-Y -0.07 79.24 67.78 0 0 0

Summation Base EQ-Y -0.03 78.95 90.97 36509 -38179 33130

COLUMN ELEMENTS


BASE 4 EQ-Y 0.04 -0.14 31.64 0 0 0

BASE 39 EQ-Y 0 -0.1 -10.58 0 0 0

BASE 50 EQ-Y -0.05 79.33 71.37 0 0 0

Summation Base EQ-Y -0.02 79.09 92.43 36502 -38160 33170


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PLATE ELEMENTS


BASE 4 EQ-X -0.87 0 18.14 0 0 0

BASE 39 EQ-X -0.08 -0.02 8.17 0 0 0

BASE 50 EQ-X 1.09 -1.02 23.5 0 0 0

Summation Base EQ-X 0.14 -1.04 49.81 18693 -20908 -1218

COLUMN ELEMENTS


BASE 4 EQ-X -0.78 0.00 18.19 0 0 0

BASE 39 EQ-X -0.08 -0.02 7.15 0 0 0

BASE 50 EQ-X 0.99 -0.98 26.48 0 0 0



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PLATE ELEMENTS


BASE 4 WIND-Y -0.29 0 6 0 0 0

BASE 5 WIND-Y -0.29 0 -7.63 0 0 0

BASE 55 WIND-Y 0 0 0 0 0 0

Summation Base WIND-Y -0.58 0 -1.63 -705 1417 252

COLUMN ELEMENTS


BASE 4 WIND-Y -0.26 0 5.23 0 0 0

BASE 5 WIND-Y -0.26 0 -6.95 0 0 0

BASE 55 WIND-Y 0 0 0 0 0 0

Summation Base WIND-Y -0.52 0 -1.72 -703 1450 256


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PLATE ELEMENTS


BASE 4 WIND-X -0.29 0 6 0 0 0

BASE 5 WIND-X -0.29 0 -7.63 0 0 0

BASE 55 WIND-X 0 0 0 0 0 0

Summation Base WIND-X -0.58 0 -1.63 -705 1417 252

COLUMN ELEMENTS


BASE 4 WIND-X -0.26 0 5.23 0 0 0

BASE 5 WIND-X -0.29 0 -6.86 0 0 0

BASE 55 WIND-X 0 0 0 0 0 0

Summation Base WIND-X -0.55 0 -1.63 -703 1450 256


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PLATE


BASE 4 EQ-X -0.87 0 18.14 0 0 0

BASE 5 EQ-X -0.85 0 -20.25 0 0 0

BASE 55 EQ-X -2.21 0 0 0 0 0

Summation Base EQ-X -3.93 0 -2.11 -2208 4179 1696

COLUMN


BASE 4 EQ-X -0.78 0 18.19 0 0 0

BASE 5 EQ-X -0.76 0 -20.76 0 0 0

BASE 55 EQ-X -2.21 0 0 0 0 0

Summation Base EQ-X -3.75 0 -2.57 -2163 4069 1619


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63

PLATE ELEMENTS


BASE 4 EQ-Y 0.05 -0.2 36.8 0 0 0

BASE 5 EQ-Y -0.03 -0.2 31.7 0 0 0

BASE 55 EQ-Y 0 -2.46 0 0 0 0

Summation Base EQ-Y 0.02 -2.86 68.49 29289 -31810 -1347

COLUME ELEMENTS


BASE 4 EQ-Y 0.04 -0.14 37.64 0 0 0

BASE 5 EQ-Y -0.02 -0.13 29.66 0 0 0

BASE 55 EQ-Y 0 -2.46 0 0 0 0

Summation Base EQ-Y 0.02 -2.72 67.3 29284 -31844 -1357


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64

PLATE ELEMENTS


BASE 25 WIND-Y -0.02 0.01 -1.37 0 0 0

BASE 39 WIND-Y -0.03 -0.01 2.39 0 0 0

BASE 52 WIND-Y 8.95 -0.01 3.24 0 0 0

Summation Base WIND-Y 8.9 -0.01 4.25 1223 -1808 -2519

COLUMN ELEMENTS


BASE 25 WIND-Y -0.02 0.01 -1.83 0 0 0

BASE 39 WIND-Y -0.03 -0.01 4.1 0 0 0

BASE 52 WIND-Y 8.13 0 2.02 0 0 0

Summation Base WIND-Y 8.08 0 4.29 1234 -1804 -2514


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65

PLATE ELEMENTS


BASE 25 WIND-X -0.02 0.01 -1.37 0 0 0

BASE 39 WIND-X -0.03 -0.01 2.39 0 0 0

BASE 52 WIND-X 8.95 -0.01 3.24 0 0 0

Summation Base WIND-X 8.9 -0.01 4.25 1223 -1808 -2519

COLUMN ELEMENTS


BASE 25 WIND-X -0.02 0.01 -1.83 0 0 0

BASE 39 WIND-X -0.03 -0.01 4.1 0 0 0

BASE 52 WIND-X 8.13 0 2.02 0 0 0

Summation Base WIND-X 8.08 0 4.29 1234 -1804 -2514


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66

PLATE ELEMENTS


BASE 25 EQ-Y 0.02 -0.06 1.43 0 0 0

BASE 39 EQ-Y 0 -0.09 -13.61 0 0 0

BASE 52 EQ-Y -1.68 0.9 -56.39 0 0 0

Summation Base EQ-Y -1.66 0.75 -68.57 -19743 31358 830

COLUMN ELEMENTS


BASE 25 EQ-Y 0.12 -0.07 1.72 0 0 0

BASE 39 EQ-Y 0 -0.1 -15.58 0 0 0

BASE 52 EQ-Y -1.78 0.87 -52.32 0 0 0

Summation Base EQ-Y -1.66 0.70 -66.18 -19737 31332 834


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67

PLATE ELEMENTS


BASE 25 EQ-X -0.07 0.02 -4.18 0 0 0

BASE 39 EQ-X -0.08 -0.02 8.17 0 0 0

BASE 52 EQ-X 30.21 -0.03 11.75 0 0 0


COLUMN ELEMENTS


BASE 25 EQ-X -0.07 0.02 -3.89 0 0 0

BASE 39 EQ-X -0.08 -0.04 9.67 0 0 0

BASE 52 EQ-X 30.21 0 9.89 0 0 0



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68

PLATE ELEMENTS


BASE 25 EQ-X -0.07 0.02 -4.18 0 0 0

BASE 39 EQ-X -0.08 -0.02 8.17 0 0 0

BASE 52 EQ-X 30.21 -0.03 11.97 0 0 0


COLUMN ELEMENTS


BASE 25 EQ-X -0.07 0.02 -4.23 0 0 0

BASE 39 EQ-X -0.08 -0.04 9.15 0 0 0

BASE 52 EQ-X 30.47 0 9.11 0 0 0



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lxix

Figure - 1

Figure - 2

Fig: Comparative values of Base Moment due to Lateral Load (Shear Wall-1)

0

5000

10000

15000

20000

25000

30000

35000

40000

EQ-X EQ-Y

Plate

Column

5100

5200

5300

5400

5500

5600

5700

5800

5900

6000

6100

WIND-X WIND-Y

Plate

Column

Load

Ki-in

Axis (X, Y)

Axis (X, Y)

Load

Ki-in


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lxx

Figure - 1

Figure - 2


0

5000

10000

15000

20000

25000

30000

EQ-X EQ-Y

Plate

Column

0

200

400

600

800

1000

1200

1400

1600

WIND-X WIND-Y

Plate

Column

Load

Ki-in

Axis (X, Y)

Axis (X, Y)

Load

Ki-in


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lxxi

Figure - 1

Figure - 2


0

5000

10000

15000

20000

EQ-X EQ-Y

Plate

Column

0

500

1000

1500

2000

WIND-X WIND-Y

Plate

Column

Axis (X, Y)

Load

Ki-in

Load

Ki-in

Axis (X, Y)


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lxxiii

Findings of the study are as follows:

1. Values are closed :analyzing of Plate shear wall and column shear wall

structures we have found base moment values are very closed.

2. Frame Methods are more accurate: according to analysis of two

methods that we have got more accurate results in frame method as a

alternate for plate element method.

3. Economical And Memory Efficient: the frame element method is

more economical and memory efficient.

4. Frame analysis method is very simple rather than plate element method.

Recommendation:

The study is used for building structure, similar study may be done for

Bridge structure.

We have done this method by static analysis. Dynamic analysis should

be used to analysis the structures to have a comparative result .


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REFERENCES

[1] Stafford Smith, B., and Coull A., Tall Building Structures: Analysis and

Design, John Wiley and Sons, 1991.

[2] Taranath, B. S., Structural Analysis and Design of Tall Buildings, McGraw-

Hill Company, 1988.

[3] Wilson, E. L., Dovey, H. H. and Habibullah, A., ETABS, Three

Dimensional Analysis of Building Systems, Computers and Structures Inc.,

Berkeley, California, USA.

[4] MacLeod, I. A., Analytical Modeling of Structural Systems, Ellis Horwood

Limited, 1990.

[5] Response of Buildings to Lateral Forces, ACI Committee Report, SP- 97,

American Concrete Institute,

[6] Rutenberg, A. and Eisenberger, M., Simple Planar Modeling of

Asymmetric Shear Buildings for Lateral Forces, Computers and Structures,

Vol.24, No.6, 1986: 885-891.

[7] Smith, B. S. and Cruvellier, M., A Planar Model for the Static and

Dynamic Analysis of Asymmetric Building Structures, Computers and

Structures, Vol.48, No.5, 1993: 951-956.

[8] Wilson, E. L. and Dovey, H. H. Three Dimensional Analysis of Building

Systems - TABS, Report No. EERC 728, College of Engineering,

University of California, Berkeley, California, December 1972.

[9] Hoenderkamp, J. C. D., Simplified Analysis of Asymmetric High Rise

Structures with Cores, The Structural Design of Tall Buildings, Vol.11,

2002: 93-107.

[10] Wilson, E. L., Dovey, H. H. and Habibullah, A., TABS90, Three

Dimensional Analysis of Building Systems, Computers and Structures Inc.,

Berkeley, California, USA, 1994.

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