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A

PROGRESS REPORT

ON

“Parametric study of multi storied R.C.C flat slab structure under seismic effect having different plan aspect ratio and slenderness ratio.”

This progress work is submitted in partial fulfillment of the requirements for the completion of the project & dissertation work.

(Session 2015-2016)

. Submitted by .Shubham S. Borkar

Sourabh kumar

. SUPERVISOR .Prof. Sudhir kapgate

( Department of civil engineering)

DEPARTMENT OF CIVIL ENGINEERING

NAGPUR INSTITUTE OF TECHNOLOGY,NAGPUR

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CERTIFICATE

This is to certify that progress work of the project work entitled

“Parametric study of multi storied R.C.C flat slab structure under seismic

effect having different plan aspect ratio and slenderness ratio.”

. Submitted by .Shubham Borkar

Sourabh kumar

This progress work , as a part and parcel of the entire project work, completed by Shubham

Borkar & Sourabh kumar under my supervision and submitted in partial fulfillment of the

requirement for the completion of the project work in the Academic Year 2015-2016

. Prof. Sudhir kapgate .(Department of Civil Engineering, NIT)

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INDEX

CONTENT PAGE NO.

Certificate II

Abstract -

Chapter 1: Aim & Objective 4-5

Chapter 2: Introduction 6-7

Chapter 3: Assumptions 8-9

Chapter 4: Plan Aspect ratio 10

Chapter 5: Slenderness ratio 11

Chapter 6: Literature Survey 12-13

Chapter 7: Methodology 14

References 15

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AIM

"Parametric study of multi storied R.C.C. flat slab structure under seismic effect

having different plan aspect ratio and slenderness ratio."

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OBJECTIVES

To calculate design lateral forces on multi-storied R.C.C. Flat slab structure with regular building

configuration in plan but different aspect ratio using “Response Spectrum Analysis.”

To calculate and study the response of structure situated in seismic zone IV and their comparison.

To determine limit aspect ratio and slenderness ratio for safe and stable structure.

To perform analysis using ETABS for static and dynamic analysis.

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INTRODUCTIONDefinition of flat slab :

Flat slab is a reinforced concrete slab supported

By columns with or without drops & column

Head.

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COMPONENTS OF FLAT SLABS

Drops: To resist the punching shear which is predominant at the contact of slab and column

support, the drop dimension should not be less than one -third of panel length in that direction.

Column heads: Certain amount of negative moment is transferred from the slab to the column at

the support. To resist this negative moment the area at the support needs to be increased .This is

facilitated by providing column capital/heads flat slab.

FLAT SLAB WITH DROP PANEL & COLUMN HEAD

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ASSUMPTIONS

STRUCTURE Multi- Storied R.C.C. Flat slab Structure

NUMBER OF STOREY 11

PLAN DIMENSIONS

• AREA 1200 m2

• COLUMN SPACING

IN X DIRECTION 6m

IN Y DIRECTION 6m

• FLOOR TO FLOOR HEIGHT 3.6m

• COLUMN SIZE (600 mm X 600 mm)

• SLAB THICKNESS 300 mm

• DROP THICHNESS 150mm

• DROP SIZE (1.25mX1.25m)

LOADING

• DEAD LOAD As Per IS 875:1987 ( Part 1)

• LIVE LOAD As Per IS 875:1987 ( Part 2 )

• AT TYPICAL FLOOR 4.0 kN/m2

• FLOOR FINISH 1.0 kN/m2

DATA FOR SEISMIC ANALYSIS

• EARTHQUAKE LOAD As Per IS 1893 (Part 1)-2002

• TYPE OF FOUNDATION Isolated Column Footing

• DEPTH OF FOUNDATION 3.5m

• TYPE OF SOIL Type II, Medium As Per IS 1893

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• BEARING CAPACITY OF SOIL 200 kN/m2

• PERCENTAGE DAMPING 0.5%

• TYPE OF FRAME Special moment resisting Frame

METHOD OF ANALYSIS RESPONSE SPECTRUM METHOD

LOAD CASES

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PLAN ASPECT RATIO (L/B)

• AREA CONSTANT = 1200 M2

• TABLE MODEL GROUP FOR ASPECT RATIO (L:B)

MAIN GROUP

ASPECT RATIO

LENGTH WIDTH COLUMN SPACING

  L : B L (m) B(m) X(m) Z(m)

M1 1 35 35 6 6

M2 2 49 25 5.85 5.5

M3 3 60 20 5 6

M4 4 60 15 6 5

M5 5 90 18 6.25 6

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SLENDERNESS RATIO (H/B)

• Various slenderness ratio can be obtained by changing no. Of storey & keeping width of building

constant

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TABLE MODEL FOR SLENDERNESS RATIO (H:B)

SR.NO MODEL

GROUP

MODEL ASPECT

RATIO

NO. OF

STOREY

STOREY

HEIGHT

SLENDERNESS

RATIO (L:B) G + 3.60 (H:B)

1

M1

M11

1

3 14.40 0.41

M12 5 21.60 0.61 2

M13 7 28.80 0.82 3

M14 9 36.00 1.03 4

M15 11 43.20 1.23 5

6

M2

M21

2

3 14.40 0.57

7 M22 5 21.60 0.86

8 M23 7 28.80 1.15

9 M24 9 36.00 1.44

10 M25 11 43.20 1.73

11

M3

M31

3

3 14.40 0.72

12 M32 5 21.60 1.08

13 M33 7 28.80 1.44

14 M34 9 36.00 1.8

15 M35 11 43.20 2.16

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TABLE MODEL FOR SLENDERNESS RATIO (H:B)contd.

SR.NO MODEL GROUP

MODEL ASPECT RATIO

NO. OF STOREY

STOREY HEIGHT

SLENDERNESS RATIO

(L:B) 3.60 (H:B)

16

M4

M41

4

3 14.40 0.96

17 M42 5 21.60 1.44

18 M43 7 28.80 1.92

19 M44 9 36.00 2.4

20 M45 11 43.20 2.88

21

M5

M51

5

3 14.40 0.8

22 M52 5 21.60 1.2

23 M53 7 28.80 1.6

24 M54 9 36.00 2

25 M55 11 43.20 2.4

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ANALYSIS OF 11 STOREY R.C. STRUCTURE

PLAN ASPECT RATIO (L/B)= 1

SLENDERNESS RATIO (H/B)= 0.96

ANALYSIS OF G+11 STOREY R.C. STRUCTURE

PLAN

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LITERATURE SURVEY

S.S. Patil, Rupali A. Sigi(2014) [1]“Flat Slab Construction in India”:

This paper deals with the different type of RCC flat slab structure and design of flat slab with the

help of IS 456:2000 and ACI-381(2) codes.

Conclusion:-

• Design of conventional R.C.C flat plate/slab in India, utilizing Indian codes, has many

shortcomings, which have to be addressed and revised soon.

• Conventional R.C.C structure should be the preferred choice for spans up to 10 meters.

• Until then indian engineers will continue to use indian codes in combination with other

standards like the aci, bs or euro code to design and analyze flat slabs/plates .

Rucha.S.Banginwar, M.R.Vyawahare, P.O.Modani, [2] “Effect of Plan Configurations

on the Seismic Behaviour of the structure By Response Spectrum Method”

• To evaluate the effect of plan configurations on the response of structure by

RSM(response spectrum method).

• The IS-1893 (Part I: 2002) guidelines and methodology are used to analyse the problem.

• Behaviour of different geometrical configurations of structure which are located in the

same area during earthquake by RSM.

• More emphasis is made on the plan configurations and its is analysis by RSM.

Conclusion:-

• Plan configurations of structure has significant impact on the seismic response of

structure in terms of displacement, story drift, story shear. The torsion and displacements

were obtained on higher side in some shapes in comparison to other.

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Prof. K S Sable, Er. V A Ghodechor, Prof. S B Kandekar, [3]“Comparative Study of

Seismic Behavior of Multistory Flat Slab and Conventional Reinforced Concrete

Framed Structures”

• Studied conventional R.C.C building and flat slab building for different floor height.

• The effect of seismic load has been studied for the two types of building with different

height.

• Observation includes behaviour of structure under effect of seismic loading in terms

of changes in natural time period, base shear, sway moments and column axial forces

Conclusion:-

• The natural time period increases as the height of building ( No. of stories) increases,

irrespective of type of building viz. conventional structure, flat slab structure and flat slab

with shear wall. However, the time period is same for flat slab structure and flat slab with

shear wall.

Mohit Sharma and Dr. Savita Maru (2014), [4]“Dynamic Analysis of Multistoried Regular

Building”:

• Performed the seismic analysis on G+30 storied regular building using STAAD Pro

V8i.

• Performed analysis with both static and a dynamic method as per the parameters

mentioned in IS 1893 2002 part I.

• Compared between two methods of analysis on the basis of Axial Forces, Torsion

and Moment at different nodes and beam.

Conclusion:-

• Result obtained for Dynamic Analysis were higher that the values as obtained by

Static Analysis for the same points and conditions.

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METHODOLOGY

SR.NO SEMESTER ACTIVITY DURATION

1. VII Review of existing literature by different research 1 month

2. VII Study of is 1893:2002 and learning Software ETABS 3 month

3. VII Formulating the assumption stating the scope of

project by considering various parameter

1 month

4. VIII Modeling and analysis of the structure with the help

of software

1 month

5. VIII Comparison of the data obtained after analysis 2 month

6. VIII Understanding the results of analysis, formulating

Conclusion and further recommendation keeping

scope of study in mind

2 month

7. VIII Dissertation writing 1 month

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REFRENCES

• I.S. 456-2000, Indian standard code of practice for plain and reinforced concrete, bureau of indian

standard, new Delhi.

• Basics of Structural Dynamics & ASEISMIC Design by S.R Damodarasamy & S. Kavitha

• Paz. Mario. “Structural dynamics" theory and computation, CBS, publishers and distributors

dayaganj, new delhi.

• Bis-1893, criteria for earthquake resistant design of structures-part-1, general provisions and

buildings, bureau of indian standards, new delhi -2002.

• I.S-13920."Ductile detailing of reinforced structures subjected to seismic force" code of practice

bureau of indian standards, new delhi -1993.

• I.S 4326 – 1993, earthquake resistant design and construction of buildings - code of practice,

bureau of indian standard, new delhi

• SP-16-1980- design aids for reinforced concrete to is-456-1978-bureau of indian standards, new

delhi.

• IS-875-1987.".Indian standard code of practice for structural safety loadings standards Part-1, 2"

Bureau of Indian Standards, New Delhi.

Www.Nicee.Org, the national information centre of earthquake engineering(nicee - established

1999) .

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THANK YOU