The document summarizes the objectives, assumptions, and analysis methodology for a project studying the seismic response of multi-story reinforced concrete flat slab structures with varying plan aspect ratios and slenderness ratios. The objectives are to calculate seismic design forces, study responses in seismic zone IV, determine safe aspect and slenderness ratios, and perform analysis using ETABS. Models are defined for 5 groups of aspect ratios from 1 to 5 and slenderness ratios ranging from 0.48 to 3.32 over 3 to 11 story buildings. Response spectrum analysis is used to analyze sample structures and modal periods, frequencies, and participation factors are presented.

1. NAGPUR INSTITUTE OF TECHNOLOGY, NAGPUR
(Department of civil engineering Session 2015-16)
3rd
Project seminar on
“Parametric study of multi storied R.C.C flat slab structure
under seismic effect having different plan aspect ratio and
slenderness ratio.”
Submitted by
Sourabh Kumar
Shubham Borkar
Under the guidance
Prof. Sudhir Kapgate

2.  Aim
 Objective
 Assumptions
 Analysis
 Methodology
 References
CONTENTS

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

4. OBJECTIVE
 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.

5. ASSUMPTIONS
 STRUCTURE Multi-Storey Flat-slab R.C. Structure
 PLAN DIMENSIONS
 AREA 900 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 30 30 6 6
M2 2 41 22 5.85 5.5
M3 3 50 18 5 6
M4 4 60 15 6 5
M5 5 75 12 6.25 6

6.  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 0.48
2 M12 5 21.60 0.72
3 M13 7 28.80 0.96
4 M14 9 36.00 1.2
5 M15 11 43.20 1.44
6
M2
M21
2
3 14.40 0.69
7 M22 5 21.60 1.03
8 M23 7 28.80 1.37
9 M24 9 36.00 1.71
10 M25 11 43.20 2.06
11
M3
M31
3
3 14.40 0.85
12 M32 5 21.60 1.27
13 M33 7 28.80 1.69
14 M34 9 36.00 2.12
15 M35 11 43.20 2.54

7. • 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 1.11
22 M52 5 21.60 1.66
23 M53 7 28.80 2.22
24 M54 9 36.00 2.77
25 M55 11 43.20 3.32

8.  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
BEARING CAPACITY OF SOIL 200 kN/m2
AVERAGE THICKNESS OF
FOOTING 0.9 m
IMPORTANCE FACTOR 1
PERCENTAGE DAMPING 5%
TYPE OF FRAME Special moment resisting Frame
 METHOD OF ANALYSIS RESPONSE SPECTRUM METHOD
 LOAD CASES

9. ANALYSIS OF 11 STOREY R.C. STRUCTURE
PLAN ASPECT RATIO (L/B)= 1
SLENDERNESS RATIO (H/B)= 1.32
PLAN ELEVATION

10. ANALYSIS DATA
TABLE: Modal Periods and Frequencies
Case Mode Period Frequenc
y
Circular
Frequenc
y
Eigen
value
sec cyc/sec rad/sec rad²/sec²
Modal1 1 3.144 0.318 1.9982 3.9928
Modal1 2 3.144 0.318 1.9982 3.9928
Modal1 3 2.91 0.344 2.1595 4.6633
Modal1 4 1.005 0.995 6.2531 39.1011
Modal1 5 1.005 0.995 6.2531 39.1011
Modal1 6 0.927 1.079 6.7791 45.956
Modal1 7 0.559 1.789 11.2405 126.3491
Modal1 8 0.559 1.789 11.2405 126.3491
Modal1 9 0.513 1.947 12.2363 149.726
Modal1 10 0.366 2.736 17.1899 295.4918
Modal1 11 0.366 2.736 17.1899 295.4918
Modal1 12 0.333 3 18.8526 355.4189

11. ANALYSIS DATA
TABLE: Modal Participation Factors
Case Mode Period UX UY UZ RX RY RZ
Modal
Mass
Modal
Stiffness
sec kN-m kN-m kN-m kN-m kN-m kN-m kN-m-s² kN-m
Modal1 1 3.144 -3.7E-05 -0.00012 0 0.685363 -0.21191 0 0.000001 3.99E-06
Modal1 2 3.144 0.000118 -3.7E-05 0 0.211908 0.685363 0 0.000001 3.99E-06
Modal1 3 2.91 0 0 0 0 0 1.579182 0.000001 4.66E-06
Modal1 4 1.005 -1.2E-05 -4.2E-05 0 -1.08592 0.309726 0 0.000001 0.00004
Modal1 5 1.005 0.000042 -1.2E-05 0 -0.30973 -1.08592 0 0.000001 0.00004
Modal1 6 0.927 0 0 0 0 0 0.556161 0.000001 0.00005
Modal1 7 0.559 0.000009 0.000026 0 0.388335 -0.12955 0 0.000001 0.00013
Modal1 8 0.559 0.000026 -9E-06 0 -0.12955 -0.38834 0 0.000001 0.00013
Modal1 9 0.513 0 0 0 0 0 -0.35457 0.000001 0.00015
Modal1 10 0.366 -6E-06 -0.00002 0 -0.4274 0.132312 0 0.000001 0.0003
Modal1 11 0.366 -0.00002 0.000006 0 0.132312 0.427403 0 0.000001 0.0003
Modal1 12 0.333 0 0 0 0 0 -0.26881 0.000001 0.00036

12. ANALYSIS OF 9 STOREY R.C. STRUCTURE
PLAN ELEVATION
PLAN ASPECT RATIO (L/B)= 1
SLENDERNESS RATIO (H/B)= 1.08

13. ANALYSIS DATA
TABLE: Modal Periods and Frequencies
Case Mode Period
Frequenc
y
Circular
Frequenc
y
Eigen
value
sec cyc/sec rad/sec rad²/sec²
Modal 1 2.091 0.478 3.0042 9.0255
Modal 2 2.091 0.478 3.0042 9.0255
Modal 3 1.951 0.513 3.2207 10.3732
Modal 4 0.643 1.555 9.7714 95.4812
Modal 5 0.643 1.555 9.7714 95.4812
Modal 6 0.595 1.681 10.5624 111.5642
Modal 7 0.341 2.934 18.4369 339.9187
Modal 8 0.341 2.934 18.4369 339.9187
Modal 9 0.313 3.195 20.0757 403.0329

14. ANALYSIS DATA
TABLE: Modal ParticipationFactors
Case Mode Period UX UY UZ RX RY RZ Modal Mass Modal Stiffness
sec kN-m kN-m kN-m kN-m kN-m kN-m kN-m-s² kN-m
Modal 1 2.091 -0.000024 -0.000078 0 0.259803 -0.080278 0 0.000001 0.00001
Modal 2 2.091 0.000078 -0.000024 0 0.080278 0.259803 0 0.000001 0.00001
Modal 3 1.951 0 0 0 0 0 1.040807 0.000001 0.00001
Modal 4 0.643 -0.000007 -0.000023 0 -0.660127 0.203914 0 0.000001 0.0001
Modal 5 0.643 -0.000023 0.000007 0 0.203914 0.660127 0 0.000001 0.0001
Modal 6 0.595 0 0 0 0 0 -0.300204 0.000001 0.00011
Modal 7 0.341 -0.000004 -0.000012 0 -0.170945 0.052852 0 0.000001 0.00034
Modal 8 0.341 -0.000012 0.000004 0 0.052852 0.170945 0 0.000001 0.00034
Modal 9 0.313 0 0 0 0 0 -0.159072 0.000001 0.0004

15. ANALYSIS OF 7 STOREY R.C. STRUCTURE
PLAN ELEVATION
PLAN ASPECT RATIO (L/B)= 1
SLENDERNESS RATIO (H/B)= 0.84

16. ANALYSIS DATA
TABLE: Modal Periods and Frequencies
Case Mode Period
Frequenc
y
Circular
Frequenc
y
Eigen
value
sec cyc/sec rad/sec rad²/sec²
Modal 1 1.993 0.502 3.152 9.9354
Modal 2 1.993 0.502 3.152 9.9354
Modal 3 1.834 0.545 3.4264 11.7399
Modal 4 0.6 1.666 10.467 109.5573
Modal 5 0.6 1.666 10.467 109.5573
Modal 6 0.551 1.816 11.4107 130.2035
Modal 7 0.316 3.162 19.8688 394.7709

17. ANALYSIS DATA
TABLE: ModalParticipationFactors
Case Mode Period UX UY UZ RX RY RZ ModalMass ModalStiffness
sec kN-m kN-m kN-m kN-m kN-m kN-m kN-m-s² kN-m
Modal 1 1.993 0.000032 0.000093 0 -0.345354 0.118783 0 0.000001 0.00001
Modal 2 1.993 -0.000093 0.000032 0 -0.118783 -0.345354 0 0.000001 0.00001
Modal 3 1.834 0 0 0 0 0 -1.257043 0.000001 0.00001
Modal 4 0.6 -0.000012 -0.000034 0 -0.544136 0.187623 0 0.000001 0.00011
Modal 5 0.6 0.000034 -0.000012 0 -0.187623 -0.544136 0 0.000001 0.00011
Modal 6 0.551 0 0 0 0 0 -0.459881 0.000001 0.00013
Modal 7 0.316 0.000008 0.000022 0 0.220083 -0.078195 0 0.000001 0.00039

18. ANALYSIS OF 5 STOREY R.C. STRUCTURE
PLAN PLAN
PLAN ASPECT RATIO (L/B)= 1
SLENDERNESS RATIO (H/B)= 0.6

19. ANALYSIS DATA
TABLE: Modal Periods and Frequencies
Case Mode Period
Frequenc
y
Circular
Frequenc
y
Eigen
value
sec cyc/sec rad/sec rad²/sec²
Modal 1 0.926 1.08 6.7849 46.0343
Modal 2 0.926 1.08 6.7849 46.0343
Modal 3 0.854 1.172 7.3616 54.1939
Modal 4 0.275 3.642 22.882 523.5882
Modal 5 0.275 3.642 22.882 523.5882

20. ANALYSIS DATA
TABLE: ModalParticipationFactors
Case Mode Period UX UY UZ RX RY RZ
Modal
Mass
Modal
Stiffness
sec kN-m kN-m kN-m kN-m kN-m kN-m kN-m-s² kN-m
Modal 1 0.926 -1.8E-05 -5.4E-05 0 0.144825 -0.04853 0 0.000001 0.00005
Modal 2 0.926 -5.4E-05 0.000018 0 -0.04853 -0.14483 0 0.000001 0.00005
Modal 3 0.854 0 0 0 0 0 -0.73109 0.000001 0.00005
Modal 4 0.275 0.000007 0.000021 0 0.227772 -0.07777 0 0.000001 0.00052
Modal 5 0.275 0.000021 -7E-06 0 -0.07777 -0.22777 0 0.000001 0.00052

21. ANALYSIS OF 3 STOREY R.C. STRUCTURE
PLAN ELEVATION

22. ANALYSIS DATA
TABLE: Modal Periods and Frequencies
Case Mode Period Frequency Circular Frequency
Eigen
value
sec cyc/sec rad/sec rad²/sec²
Modal 1 0.771 1.297 8.1476 66.384
Modal 2 0.771 1.297 8.1476 66.384
Modal 3 0.704 1.421 8.9275 79.7001

23. ANALYSIS DATA
TABLE: ModalParticipationFactors
Case Mode Period UX UY UZ RX RY RZ ModalMass ModalStiffness
sec kN-m kN-m kN-m kN-m kN-m kN-m kN-m-s² kN-m
Modal 1 0.771 -0.00002 -0.000062 0 0.095284 -0.030362 0 0.000001 0.00007
Modal 2 0.771 -0.000062 0.00002 0 -0.030362 -0.095284 0 0.000001 0.00007
Modal 3 0.704 0 0 0 0 0 0.82484 0.000001 0.00008

24. 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 IS 13920 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

25. • Prof. K S Sable, Er. V A Ghodechor, Prof. S B Kandekar, “Comparative Study of Seismic
Behavior of Multistory Flat Slab and Conventional Reinforced Concrete Framed
Structures”, International Journal of Computer Technology and Electronics Engineering
(IJCTEE) Volume 2, Issue 3, June 2012
• Rucha.S.Banginwar, M.R.Vyawahare, P.O.Modani, “Effect of Plan Configurations on the
Seismic Behavior of the structure By Response Spectrum Method” ,International Journal
of Engineering Research and Applications(IJERA),Vol2,May-June2012
• Arun Solomon A, Hemalatha G, “Limitation of irregular structure for seismic response”,
International Journal Of Civil And Structural Engineering Volume 3, No 3, 2013
• Mohit Sharma and Dr. Savita Maru(2014), “Dynamic Analysis of Multistoried Regular
Building” , Journal of Mechanical and Civil Engineering (IOSR-JMCE), Volume 11, Issue
1 Ver. II.
• Mayuri D. Bhagwat and Dr.P.S.Patil(2014), “Comparative study of performance of rcc
multistory building for Koyna and Bhuj earthquakes”, International Journal of Advanced
Technology in Engineering and Science Volume No.02, Issue No. 07.
REFERENCES

26. • Paz. Mario. “Structural Dynamics" theory and Computation, CBS, Publishers and
Distributors Dayaganj, New Delhi.
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Concepts in Earthquake Behaviour of Buildings”, Gujarat State Disaster Management
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• 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. 456-2000, Indian Standard Code of Practice for Plain and Reinforced Concrete, Bureau
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• IS-875-1987.".Indian standard code of practice for structural safety loadings standards
Part-1, 2" Bureau of Indian Standards, New Delhi.
• I.S 4326 – 1993, Earthquake Resistant Design And Construction Of Buildings - Code Of
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27. THANK
YOU