Ijri cce 02 0013

International Journal of Research and Innovation (IJRI)

International Journal of Research and Innovation (IJRI) 1401-1402

MODELLING OF TALL BUILDINGS WITH DIFFERENT SLAB CONDITIONS

Ch.sindhuja1, K. Mythili2 1 Research Scholar, Department of Civil Engineering, Aurora's Scientific Technological and Research Academy, Hyderabad India.

2 Assistant professor , Department of Civil Engineering, Aurora's Scientific Technological and Research Academy, Hyderabad India.

Abstract Modelling of multi storied building as a frame structure which is supported by beams and columns is matter of course now a days.

We consider the structural strength which is provided by the walls and slabs for the normal height of buildings. As the building height go on increases the forces upon the building also increases with the addition of wind and seismic loads which we call as dynamic loadings depending upon the different slab condition.

In this thesis modelling and structural analysis of 41 stored building have been performed to investigate the effect of considering the slab with different plate condition (shell, plate, membrane) subjected to dynamic load studied. The study is further reinforced by considering factors such as model considering with infill and diaphragm, model considering with diaphragm and without infill, model considering with infill and without diaphragm action, model with no diaphragm action and no infill effect. Using ETabs.

*Corresponding Author: Ch.sindhuja, Research Scholar, Department of Civil Engineering, Aurora's Scientific Technological and Research Academy, Hyderabad India.

Published: August 11, 2015 Review Type: peer reviewed Volume: II, Issue : III Citation: Ch.sindhuja , Research Scholar (2015) "MODELLING OF TALL BUILDINGS WITH DIFFERENT SLAB CONDITIONS"

INTRODUCTION General In developing countries like India, demand of high rise buildings is increasing day by day due to growing population and lack of land in urban areas. From structural engineer’s point of view, high rise multi-storied building is the one that by virtue of its height is affected by lateral forces to an extent that they play an important role in the structural design. In this type of buildings, wind and seismic loads play a predominant role. Hence the lateral stability is most important for high rise building.

Earthquakes are one of the nature’s greatest hazards to life on this planet. They are the least understood of the natural hazards and in the early days were looked upon as supernatural events. The annual losses due to earthquakes are very large in many parts of the world. The human and economic losses resulting from severe earthquakes are due to failure of human-made facilities such as buildings, bridges etc.

In recent years a powerful earthquake was struck the Kutch region of the province of Gujarat at 8:46 a.m. on 26th of January 2001, with a magnitude of 6.7. The epi-

centre of the earthquake was located at 50 km northeast of the town of Bhuj. This earthquake ranks as one of the most destructive events recorded so far in India in terms of death, damage to infrastructure and devastation in last ten years. Damage due this earthquake was estimated at Rs: 21300 crores. The number of injured people is reported to be 166000, of which 20700 suffered serious injuries.

It is estimated that about 370000 houses and huts were completely destroyed. After investigation it was revealed that damage of various structures is due to deficiency in design, planning practice, analysis, and even poor quality of construction and poor detailing.

In this chapter, introduction of membrane, plates and shells were discussed; this chapter also deals with the types of plates and shells. Uses of these elements and their differences are focused.

Plates Plates are considered to be any essentially flat two dimensional structural components such as floor slab, flat roof which are made up of metal, the only difference between the plates and slab is only the material used. The bending property of plate mainly depends on the thickness of plates as compared with the other dimensions.

The following are the kinds of plates which are distinguished below • Thin plates with small deflection • Thin plate with large deflections • Thick plate Thin plates with small deflections: If the deflections are very small in comparison with its thickness h, a very satisfactory approximate theory of bending of plate by lateral loads can be developed by making following assumptions

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There is no deformation in the middle plane of the plate, this plane remains nuetral.

Thin plates with large deflections: Points of plate lying initially on a normal –to-the-middle of the plate remain normal-to-the-middle of the surface of plate after bending.

The normal stresses in the direction transverse to the plate can be disregarded.

Thick plates: In the case of highly concentrated plates thick plate theory should be applied, theory considers the three dimensional problem of elasticity.

Shell A curved surface having small thickness compared to the radius and other dimensions. shells or skin space roofs are preferable to plane roofs since they can be used to cover large floor spaces with economical use of materials of construction. These are generally adopted for hangers, sports auditoriums, exhibition halls, industrial buildings and a variety of other large span structures where uninterrupted floor space is required. Recent advances include the construction of shell structures using prefabricated shell elements.

Classification of Shells Shells are broadly classified into major groups which are generally grouped under three categories designated as 1. Shells of revolution These are obtained when a plane curve is rotated about the axis of symmetry. the common examples of shells of revolution are circular dome, the cone and the paraboloid of revolution.

Advantages of Shell Structures • Thickness is small relative to other dimensions • Shell structures would weigh less than other structure • Attraction of elegant simplicity of curved shell forms that utilize the Natural strength and stiffness of shell form with great economy in the use of material.

• Continuity and Curvature- The essential ingredients of a shell structure Different Shell Structures • • • • • • • • •

Thin shell structure Folded Shell Structures Hyperbolic parabolic shell Barrel Shells Umbrella Shells Timber Shell Structures Lattice and grid shell structures Hyper & Concrete Shells Hyperbolic shells

OBJECTIVES OF THE STUDY The present work aims at the following objectives: • Study of Seismic demands of different regular R.C buildings using different area objects (shell, plate and membrane) using response spectrum method.

• To illustrate the effects of different, area objects by considering infill on the response of High-rise symmetric Buildings.

• Comparative study of analyzed area element of all seismic zones with respect to point displacement, storey drift, base shear, column forces and beam forces considering two load combinations.

• The results explained by considering three columns with different position namely corner, intermediate and interior column.

SCOPE OF THE STUDY

3. Ruled surfaces

With more and more tall buildings appearing on the skylines of our cities today, it is apparent that they have become a major factor in the growth of our society. The tall building brings with it unique problems that the professions must be aware of and must learn to solve. It is hoped that the presentations of this thesis will contribute toward a better understanding of the seismic behavior of vertical load bearing tall building and the problems associated with it.

Ruled surfaces are generated entirely by straight lines. if ate every point, a single straight line can be ruled, the surface is termed as singly ruled surface. Common examples of singly ruled surfaces are cylindrical shells and conical shells

The seismic design of tall buildings or buildings introduces new challenges that need to be met through consideration of scientific, engineering, and regulatory issues specific to the modeling, analysis, and acceptance criteria appropriate for these unique structural systems.

if at every point ,two straight lines are ruled , the surface generated is termed as doubly ruled surface. common examples of doubly ruled surface are hyperbolic paraboloid and hyperboloid of revolution of one sheet.

This thesis investigates a high-rise building incorporating tall reinforced concrete systems as it is subjected to the types of strong earthquake ground motions which can be expected in any seismic zones. The structure is evaluated in accordance with seismic code IS-1893:2002 with the help of the ETABS nonlinear version software (CSI Ltd) analysis engine .

2. Shells of translation These are formed when one curve moves parallel to itself along another curve, the planes of the two curves being at right angles to each other, elliptic paraboloid, hyperbolic paraboloid are the common examples of translation.

Application of Shell Structures • • • • •

Architecture and building Power and chemical engineering Structural engineering Vehicle body structures Composite construction

Optimization Optimization is a discipline of adjusting a process so as to optimize some specified set of parameters without violating some constraint. The most common goals are 208

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maximizing throughput, and efficiency. This is one of the major industrial decision making. The goal of optimization is to maximize one or more of the process specifications, while keeping all others within their constraints.

It is the process of adjusting one’s trading system in an attempt to make it more effective. These adjustments include changing the number of indicators used, or simply.

Taking away what doesn’t work.

Structural Modelling:

and frame –shear walls, then single idealized plane frame model of all such frames can be represented as shown in Different units, such as frames 1, frames2, etc. represent the lateral resisting frames along each line. These units are then connected at storey levels by rigid links, which simulate the enplane rigidity of floors. The finite width or core and wall are taken into account as represented by beam with rigid ends. This type of plane frames model can be analyzed by a standard plane frames programmed.

Structural modelling is concerned with describing “things” in a system and how these things are related to each other. A “thing” can be an object, a class, an interface, a package or a subsystem, which is part of the system being developed.

MATHEMATICAL MODELLING OF MULTI STOREYED RC BUILDINGS Mathematical model of a structure is its idealization by a suitable form amenable to structural analysis by a standard procedure. The most important step in the design process of a building is to create an appropriate mathematical model that will adequately represent its stiffness mass distribution and energy dissipation so that it response to earthquake could be predicted with sufficient accuracy.

The model and its degree of sophistication are dependent upon the analysis and design requirement specified in the code. Some of the common type of model employed are building are 2D plan frame model, 3D frame space frame model and reduced 3D model with three degree of freedom per storey .

PLANER MODELS Majority of typical building are structured on the basis of frame shear walls and box type of element like staircase and elevator shafts to transmit vertical and horizontal load. these elements are tied together by beams and slabs which are supposed to act as rigid or flexible diaphragms in their planes .frame and shear walls in a building are located along two orthogonal directions much of the action can be represented by plan frame idealization .therefore plane frame idealization of building is a natural choice of structural model .the various type of plan frame model employed are as

IDEALIZED PLANE FRAME MODEL EQUIVALENT SHEAR WALL FRAME MODEL In order to analyze the building with parallel frames in plan as shown in figure 3.4, an equivalent shear wall – frames models is established (khan-sbarounis, 1964).

The equivalent frames is obtained by lumping together all the frames into one bay equivalent frames, and combining all shear wall into an equivalent shear wall. This equivalent frame-shear wall system is analysed for total lateral loads on the building in the particular direction. Subsequently the forces computed in the equivalent frames are distributed to the component elements form which the equivalent frames is composed in proportion to the lateral stiffness.

PLANE FRAME MODEL OF COUPLED SHEAR WALLS The multi-storied shear walls with openings are called coupled shear walls; these can be idealized by a frame with finite joints. The coupled wall is thus represented as a frame expects that the finite width of the columns in comparison with the beam is recognized. A typical representation of coupled wall by a frame model is shown in figure.

SHEAR BEAM MODEL A shear beam model is one in which the shear force acting on any mass depend only on relative of adjacent masses .the shear beam model represented by close coupled system .

FLEXURE BEAM MODEL A flexure beam model corresponds to a typical cantilever beam with masses lumped at discrete point. This represents an example of a far-coupled system .The forces acting on any mass depends on displacement relative to all other masses of the system. An analytical model of a multi – storied building, that considers joint rotations as well as axial deformation in columns correspond to a flexural beam model.

FLEXURE BEAM MODEL IDEALIZED PLANE FRAME MODEL When the plan consists of combination of parallel frames

COUPLED SHEAR WALL 3D SPACE FRAME MODEL If the layout of the building is unsymmetrical, the building can be best analyzed by a 3D space frame model.

Any combination of frame and walls can be idealized as a space frame consisting of assemblage of beam and column elements. Each elements of a model in space frame consist of a beam element with six degree of freedom at each joint. The stiffness matrix of these beam elements is 12 *12. Any torsional effects are automatically considered in this model .The ground motions can be applied 209

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in one, two or three directions, individually or simultaneously. The analysis is best suited or non-rectangular units. Building with floating columns.

NUMERICAL STUDIES In this chapter linear static analysis and dynamic analysis are carried out to study the seismic behaviour of structure in terms of axial forces, bending moments, shear forces, displacements, Response spectrum method has been adopted in this study. Effect of building behaviour with respect to storey height, infill wall and diaphragm action have been presented in this study. The details of the building models are presented in the below sections.

Sl.no

Variable

Data

1

Type of structure

Moment Resisting Frame

2

Number of Stories

41

3

Floor height

3m

4

Live Load

5.0 kN/m2

5

WALL load

10KN/m

6

Materials

Concrete (M40) and Reinforced with HYSD bars (Fe500)

7

Size of Columns

900X900 mm

8

Size of Beams

600x400 mm in longitudinal direction 600x400 mm in transverse direction

9

Depth of slab

150mm thick

10

Specific weight of RCC

25 kN/m3

11

Zone

V

12

Importance Factor

1

13

Response Reduction Factor

5

14

Type of soil

Medium

Elevation and Isometric view of model

STRUCTURAL SYSTEMS OF THE BUILDING The foundation system is isolated footings with a depth of the Foundation being set to 3m. The column and beam dimensions are detailed in Table 4.1.In the calculation the unit weights of the materials adopted, have been taken according to the IS-875 (Part 1) and the live load consideration in loads according to IS-1893 (Part 1): 2002 i.e. 25% of the live load has to be considered if the LL > 3.5kN/m2.

Geometry of the structure and also the sections assigned.

DATA COLLECTION The building models are of 10 storey’s located in zone II, IV &V. Tables 4.0 and Table present a summary of the building parameters.

General data collection and condition assessment of building.

S.No.

Description

Information

1

Building height a.41-storey

123m

Including the foundation level

2

Number of basements below ground

0

----

3

Open ground storey

Yes

----

4

Special hazards

None

----

5

Type of building

Regular/ Irregular Space frames

IS 1893:2002 Clause 7.1

6

Horizontal floor system

Beams and slabs

----

7

Software used

ETABS

----

Plan Views of Buildings

Remarks

Isometric Views of Model

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ments, axial forces, Shear forces, and Bending moments.

The results explained by considering three columns with different position namely corner, intermediate and interior column.

GRAPHS: The results here shown which explains the behavior of nodal displacement of whole structure and also corner column, intermediate column and interior column are analyzed from the building for four different model and three slab condition separately respectively.

SUPER Dead load (FFL) 1kN/m2m2according to the data presented in the table

CORNER COLUMN OF AXIAL FORCE (KN) WITH DIAPHRAGM From the above graph line Element - It is seen that all the values are approximately same which starts from max. 19575.68 KN at bottom and 447.24 KN at top storey respectively.

Modal load case set to calculate the mode shapes.

CORNER COLUMN OF SHEAR FORCE (KN) WITH DIAPHRAGM From the above graph line Element - It is seen that all the shear force values are approximately same which starts from max.

455.32 KN at bottom and 200.84 KN at top storey respectively.

Load cases set to perform the linear static analysis.

RESULTS AND DISCUSSIONS The work in this thesis has been analyzed with different model with different categories based on infill wall and diaphragm the results has been shown below strictly following the IS codes upon necessary. The thesis has been worked very carefully so as to optimize the results and conclusions with wide models and with wide literature review.

The results have been explained here with different models and with different categorized .A total of 4 different models and with 4 different categorized has been worked here to come out with better results or with the better model comparatively.

The structural behavior of the models with different model has been taken in this thesis to come up with the model which has the better resistance to the displace-

CORNER COLUMN OF BENDING MOMENT (2)(KN-M) WITH DIAPHRAGM From the above graph line element-Bending Moment in membrane-1 has the lowest values starting from 237KN-M in top floors and 692KN-M in bottom floors compare to other models.

Here B.M in plate model has max at bottom of 653 KNM, lowest at 28th storey of 152 KN-M and Maximum of all at 40th storey

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max. 39.063 KN-M at bottom and 14.9233 KN-M at top storey.

CORNER COLUMN OF BENDING MOMENT (3) (KN-M) WITH DIAPHRAGM From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 732.296 KN-M at bottom and 241.578 KN-M at top storey respectively.

CORNER COLUMN OF BENDING MOMENT (M3)(KN-M) WITH INFILL From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 95.625 KN-M at bottom and 30.24 KN-M at top storey respectively.

CORNER COLUMN OF AXIAL FORCE (KN) WITH INFILL From the above graph line Element - It is seen that all the values are approximately same which starts from max. 20868.58KN at bottom and 377.05 KN at top storey respectively.

CORNER COLUMN OF AXIAL LOAD (KN) WITHOUT DIAPHRAGM AND INFILL. From the above graph line Element - It is seen that all the values are approximately same which starts from max. 16768.71KN at bottom and 447.26 KN at top storey respectively.

CORNER COLUMN OF SHEAR FORCE(KN) WITH INFIILL From the above graph line Element - It is seen that all the shear force values are approximately same which starts from max.

44.68 KN at bottom and 24.45 KN at top storey respectively.

CORNER COLUMN OF SHEAR FORCE (KN) WITHOUT DIAPRAGM AND INFILL From the above graph line Element - The shear force in all models is constant through wise up to 36th Storey and increases to 194.29 KN average at 40th Storey.

CORNER COLUMN OF BENDING MOMENT (M2)(KN-M) WITH INFILL From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from

CORNER COLUMN OF BENDING MOMENT (M2) (KN-M) WITHOUT DIAPRAGM AND INFILL .From the above graph line Element - The bending moment in all models is constant through wise up to 36th Storey and

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CORNER COLUMN OF BENDING MOMENT (M3) (KN-M) WITHOUT DIAPRAGM AND INFILL From the above graph line Element - The bending moment in all models is constant through wise up to 36th Storey and increases to 341.386 KN-M average at 40th Storey.

CORNER COLUMN OF BENDING MOMENT (M3) (KN-M) WITH DIAPRAGM AND INFILL From the above graph line element-Bending Moment in has the lowest values starting from 14.98KNm in top floors and 148.975KNm in bottom floors compare to other models. Here B.M in membrane model has max at bottom of 170.041 KN-M, lowest at 12th storey of 96.349 KN-M and Maximum of all at 40th storey of 42.633 KN-M.

CORNER COLUMN OF AXIAL FORCE (KN) WITH DIAPHRAGM AND INFILL From the above graph line Element - It is seen that all the values are approximately same which starts from max. 22768.58KN at bottom and 389.08 KN at top storey respectively.

INTERMEDATE COLUMN OF AXIAL FORCE (KN) WITH DIAPHRAGM From the above graph line Element - It is seen that all the values are approximately same which starts from max. 2139.02KN at bottom and 512.8 KN at top storey respectively.

CORNER COLUMN OF SHEAR FORCE WITH DIAPHRAGM AND INFILL. From the above graph line element-It indicates that the shear force in two models (plate and shell) is approximately same. Here membrane is differing from all others which starts from 84.39KN and has max value at 40th storey of 39.19KN.

CORNER COLUMN OF BENDING MOMENT (M2) (KN-M) WITH DIAPRAGM AND INFILL From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 70.189 KN-M at bottom and 20.392KN-M at top storey respectively.

INTERMEDATE COLUMN OF SHEAR FORCE WITH DIAPHRAGM From the above graph line element-Bending Moment in has the lowest values starting from 152.52KNm in top floors and 791.79KNm in bottom floors compare to other models. Here B.M in membrane model has max at bottom of 791.79 KN, lowest at 20th storey of 314.14 KN and Maximum of all at 40th storey of 253..422 KN.

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International Journal of Research and Innovation (IJRI)

INTERMEDATE COLUMN OF BENDING MOMENT (KN-M) WITH DIAPHRAGM From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 1197.649 KN-M at bottom and 138.036 KN-M at top storey respectively.

INTERMEDIATE COLUMN OF BENDING MOMENT (M2) (KN-M) WITH INFILL From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 40.744KN-M at bottom and 2.924 KN-M at top storey respectively.

INTERMEDATE COLUMN OF BENDING MOMENT (M3) (KN-M) WITH DIAPHRAGM From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 738.048 KN-M at bottom and 304.742 KN-M at top storey respectively.

INTERMEDIATE COLUMN OF BENDING MOMENT(M3)(KN-M) WITH INFILL From the above graph line Element - The bending moment in , plate and shell are same and maximum bending moment in membrane value at bottom level 125.074 suddenly decrease at 36 floor of 270 KN-M and Storey which follows to a top storey maximum value of 270.919KN-M.

INTERMEDIATE COLUMN OF AXIAL FORCE (KN) WITH INFILL From the above graph line Element - It is seen that all the values are approximately same which starts from max. 21124.73KN at bottom and 491.56 KN at top storey respectively.

INTERMEDIATE COLUMN OF SHEAR FORCE (KN) WITH INFILL From the above graph line Element - The shear force in plate and shell is approximately same and shear force in membrane has Max. Value at 40th storey of 214 KN and suddenly decreases to 142 KN at 36th Storey which follows to a Min. value of 82.85 KN

INTERMEDIATE COLUMN OF AXIAL FORCE(KN) WITHOUT DIAPHRAGM AND INFILL From the above graph line Element - It is seen that all the values are approximately same which starts from max. 513.52KN at bottom and 19240.76 KN at top storey respectively

INTERMEDIATE COLUMN OF SHEAR FORCE(KN) WITHOUT DIAPHRAGM AND INFILL From the above graph line Element - The shear force in plate and shell is approximately same and shear force in membrane has Max. value at 40th storey of 250 KN and suddenly decreases to 168.44 KN at 36th Storey which follows to a Min. value of

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International Journal of Research and Innovation (IJRI) 289.48 KN.

KN.

INTERMEDIATE COLUMN OF BENDING MOMENT(M2)(KN-M) WITHOUT DIAPHRAGM AND INFILL From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 134.872KN-M at bottom and 443.209 KN-M at top storey respectively.

INTERMEDIATE COLUMN OF BENDING MOMENT(M2)(KN-M) WITH DIAPHRAGM AND INFILL From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 72.803KN at bottom and 2.70 KN at top storey

INTERMEDIATE COLUMN OF BENDING MOMENT(M3)(KN-M) WITHOUT DIAPHRAGM AND INFILL From the above graph line Element - The bending moment in plate and shell is approximately same and shear force in membrane has Max. value at 40th storey of 306.907 KN-M and suddenly decreases to 252 KN-M at 36th Storey which follows to a Min. value of 322.583 KN-M.

INTERMEDIATE COLUMN OF BENDING MOMENT(M3)(KN-M) WITH DIAPHRAGM AND INFILL From the above graph line Element -The bending moment in , plate and shell are same and maximum bending moment in membrane value at bottom level 138.3KN-M suddenly decrease at 36 floor of 225 KN-M and Storey which follows to a top storey maximum value of 285.366KN-M.

INTERMEDIATE COLUMN OF AXIAL FORCE(KN) WITH DIAPRAGM AND INFILL From the above graph line Element - It is seen that all the values are approximately same which starts from max. 488.55KN at bottom and 23284.85 KN at top storey respectively.

INTERIOR COLUMN OF AXIAL FORCE(KN) WITH DIAPHRAGM From the above graph line Element - It is seen that all the values are approximately same which starts from max. 22047.6 KN at bottom and 571.17 KN at top storey respectively.

INTERMEDIATE COLUMN OF SHEAR FORCE(KN) WITH DIAPHRAGM AND INFILL From the above graph line Element - The shear force in plate and shell is approximately same and shear force in membrane has Max. value at 40th storey of 233.39 KN and suddenly decreases to 150.36 KN at 36th Storey which follows to a Min. value of 84

INTERIOR COLUMN OF SHEAR FORCE(KN) WITH DIAPHRAGM From the above graph line Element - It is seen that all the shear force values are approximately same which starts from max.

854.21 KN at bottom and 121.39 KN at top storey respectively.

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INTERIOR COLUMN OF BENDING MOMENT(M2)(KN-M) WITH DIAPHRAGM From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 1267.55 KN-M at bottom and 149.897 KN-M at top storey respectively.

INTERIOR COLUMN OF BENDING MOMENT(M3)(KN-M) WITH DIAPHRAGM AND INFILL From the above graph line Element - The bending moment in membrane, plate and shell is approximately same but the bending moment in membrane has Max value at 40th storey of 149.411 KN and suddenly increase to 149.411 KN at 12th Storey which follows to a Min. value of 78.786 KN.

DISCUSSION DIAPHRAGM a) Corner Column Forces

INTERIOR COLUMN OF BENDING MOMENT(M3)(KN-M) WITH DIAPHRAGM From the above graph line Element - It is seen that all the bending moment values are approximately same which starts from max. 1317.425 KN-M at bottom and 156.168KN-M at top storey respectively.

1. In diaphragm the axial force increases slightly from 0.12% to 1.4% from 4 storey to 20 storey accordingly and decreases from 1.3% to 0.41% 24 storey to 40 storey accordingly when we compare membrane with plate.

2. In diaphragm the shear force decreases slightly from 5.74% to 5.70% from 4 storey to 8 storey accordingly and increases from 5.77% to 28.12% 12 storey to 40 storey accordingly when we compare membrane with plate.

3. In diaphragm the bending moment(M2) decreases slightly from 5.58% to 5.34% from 4 storey to 8 storey accordingly ,increases in bending moment(M2) from 5.37% to 52.61% from 12 storey to 28 storey and increases in bending moment (M2) from 8.8% to 27.68% from 32 storey to 40 storey accordingly when we compare membrane with plate. b) Intermediate Column Forces

INTERIOR COLUMN OF AXIAL FORCE(KN) WITH INFILL From the above graph line Element - It is seen that all the values are approximately same which starts from max. 23578.35 KN-M at bottom and 607.41 KN-M at top storey respectively.

1. In diaphragm the axial force decreases slightly from 0.74% to 0.19% from 4 storey to 16 storey accordingly and decreases from 0.25% to 0.16% 20 storey to 40 storey accordingly when we compare membrane with plate.

2. In diaphragm the shear force decreases slightly from 4.17% to 3.57% from 4 storey to 16 storey accordingly and decreases from 39.32% to 2.05% 20 storey to 40 storey accordingly when we compare membrane with plate.

3. In diaphragm the bending moment(M2) decreases slightly from 4.11% to 0.94% from 4 storey to 40 storey accordingly when we compare membrane with plate. c) Interior Column Forces

INTERIOR COLUMN OF SHEAR FORCE(KN) WITH INFILL From the above graph line Element - It is seen that all the shear force values are approximately same which starts from max20.06 KN at bottom and 108.57 KN at top storey respectively.

1. In diaphragm the axial force increases slightly from 1.92% to 1.93% from 4 storey to 8 storey accordingly and decreases from 1.93% to 0.06% 12 storey to 40 storey accordingly when we compare membrane with plate.

2. In diaphragm the shear force decreases slightly from 5.60% to 2.72% from 4 storey to 36 storey accordingly and increases from 2.72% to 7.73% 36 storey to 40 storey accordingly when we compare membrane with plate.

3. In diaphragm the bending moment(M2) decreases slightly from 5.51% to 3.61% from 4 storey to 36 storey accordingly and increases in bending moment (M2) from 3.36% to 8.38% from 36 storey to 40 storey accordingly when we compare membrane with plate.

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INFILL a) Corner Column Forces 1. In infill the axial force decreases slightly from 0.41% to 0.35% from 4 storey to 32 storey accordingly and increases from 0.37% to 6.08% 36 storey to 40 storey accordingly when we compare membrane with plate.

2. In infill the shear force decreases slightly from 8.66% to 7.88% from 4 storey to 16 storey accordingly and increases from 8.17% to 39.50% 20 storey to 40 storey accordingly when we compare membrane with plate.

3. In infill the bending moment(M2) decreases slightly from 6.76% to 6.37% from 4 storey to 8 storey accordingly and increases in bending moment (M2) from 6.61% to 38.46% from 12 storey to 40 storey accordingly when we compare membrane with plate. b) Intermediate Column Forces 1. In infill the axial force decreases slightly from 0.40% to 0.35% from 4 storey to 40 storey accordingly when we compare membrane with plate.

2. In infill the shear force decreases slightly from 57.75% to 34.33% from 4 storey to 36 storey accordingly and increases from 34.33% to 35.20% 36 storey to 40 storey accordingly when we compare membrane with plate.

3. In infill the bending moment(M2) decreases slightly from 0.08% to 0.05% from 4 storey to 8 storey accordingly and increases from 0.09% to 16.04% from 12 storey to 40 storey accordingly when we compare membrane with plate. c) Interior Column Forces 1. In infill the axial force increases slightly from 1.47% to 1.48% from 4 storey to 8 storey accordingly, decreases from 1.47% to 1.34% from 12 storey to 32 storey accordingly and increases from 1.36% to 1.64% from 36 storey to 40 storey when we compare membrane with plate.

2. In infill the shear force decreases slightly from 23.52% to 0.97% from 4 storey to 40 storey accordingly when we compare membrane with plate.

3. In infill the bending moment(M2) decreases slightly from 12.67% to 0.41% from 4 storey to 32 storey accordingly and decreases in bending moment (M2) from 0.42% to 0.34% from 36 storey to 40 storey accordingly when we compare membrane with plate.

WITHOUT DIAPHRAGM AND INFILL a) Corner Column Forces 1. In without diaphragm and infill the axial force decreases slightly from 1.42% to 0.004% from 4 storey to 40 storey accordingly when we compare membrane with plate.

2. In without diaphragm and infill the shear force decreases slightly from 9.42% to 8.42% from 4 storey to 20 storey accordingly and increases from 8.5% to 25.7% 24 storey to 40 storey accordingly when we compare membrane with plate.

3. In without diaphragm and infill the bending moment(M2) decreases slightly from 6.45% to 8.22% from 4 storey to

20 storey accordingly and increases in bending moment (M2) from 8.28% to 25.49% from 24 storey to 40 storey accordingly when we compare membrane with plate. b) Intermediate Column Forces 1. In with diaphragm and infill the axial force decreases slightly from 7.52% to 6.52% from 4 storey to 12 storey accordingly and decreases from 6.67% to 0.95% 16 storey to 40 storey accordingly when we compare membrane with plate.

2. In with diaphragm and infill the shear force increases slightly from 39.72% to 51.27% from 4 storey to 12 storey accordingly, decreases from 47.49% to 41.99% 12 storey to 36 storey accordingly and increases from 41.99% to 52.00% from 36 storey to 40 storey when we compare membrane with plate.

3. In with diaphragm and infill the bending moment(M2) decreases slightly from 4.57% to 0.49% from 4 storey to 8 storey accordingly and decrease from 1.08% to 0.43% from 12 storey to28 storey accordingly and increases from 0.80% to 39.9% from 32 storey to 40 storey accordingly when we compare membrane with plate.

CONCLUSIONS The following conclusions are drawn from the present study (1) Maximum B.M in x-direction is more in case of structural element modelled as membrane and shell with diaphragm , infill, without diaphragm and infill and with diaphragm and infill as compared with that of plate with diaphragm, infill, without diaphragm and infill and with diaphragm and infill.

(2) Maximum B.M in x-direction is more in case of structural element modelled as membrane and shell with diaphragm , infill, without diaphragm and infill and with diaphragm and infill as compared with that of plate with diaphragm, infill, without diaphragm and infill and with diaphragm and infill.

(3) Maximum Shear force is more in case of structural element modelled as membrane and shell with diaphragm , infill, without diaphragm and infill and with diaphragm and infill as compared with that of plate with diaphragm, infill, without diaphragm and infill and with diaphragm and infill.

(4) Maximum axial force is more in case of structural element modelled as membrane and shell with diaphragm , infill, without diaphragm and infill and with diaphragm and infill as compared with that of plate with diaphragm, infill, without diaphragm and infill and with diaphragm and infill.

(5) Maximum displacement is more in case of structural element modelled as membrane and shell with diaphragm, infill, without diaphragm and infill and with diaphragm and infill as compared with that of plate with diaphragm, infill, without diaphragm and infill and with diaphragm and infill.

In all aspects (i.e., using membrane, shell and plate with conditions, with diaphragm, infill, without diaphragm and infill and with diaphragm and infill) using plate is more preferable and economical.

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International Journal of Research and Innovation (IJRI)

Author

REFERENCES 1. IS 456-2000 “Code of Practice for Plain and Reinforced Concrete.” Bureau of India standards 2. IS 1893-2002 “Criteria for earthquake resistant design of structures.” Bureau of India standards 3. Pankaj Agarwal and Manish Shrikhande, (2006) “Earthquake Resistant Design of Structures”, Prentice Hall of India 4. James O Malley (2007) “Acceptance Criteria For Seismic Design and Analysis of Tall Building” 5. Kyoung Sun Moon(2007) Structural for Tall Building”

“Optimal Configuration of

Ch.sindhuja, Research Scholar, Department of Civil Engineering, Aurora's Scientific Technological and Research Academy, Bandlaguda,Hyderabad, India.

6. J.W. Wallace (2007) “ Modelling Issue For Tall Reinforced Concrete Core Wall Building” 7. Zhang N (1990) “Modelling of Structural Response and Optimization of Structural Control System” 8. B.F. Spencer(1989) “Vibration Mitigation of Tall Building :Modelling and Analysis of Open Loop Control” 9. B.Taranath (1988) structural analysis and design of tall building

K.Mythili, Assistant Professor, Department of Civil Engineering, Aurora's Scientific Technological and Research Academy, Bandlaguda,Hyderabad, India.

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