1. PRESENTATION ON
A Comparative Study of
Static and Response Spectrum
Analysis
of a RC Building

2. TAMEEM SAMDANEE 10.01.03.127
JOHINUL ALAM 10.01.03.036
MD. ZAHIDUL ISLAM 10.01.03.142
ABU SYED MD. TARIN 10.01.03.020
UNDER THE SUPERVISION OF
ZASIAH TAFHEEM
ASSISTANT PROFESSOR
DEPARTMENT OF CIVIL ENGINEERING, AUST

3.  To determine the natural period of vibrations for different mode shapes of
the comprehensive 3D using modal analysis techniques.
 To determine the storey-displacements and storey-drifts for each storey of
a six storied building.
 To determine the base shears of the building under seismic loading.
 To determine the column shear forces and bending moments following the
Equivalent Static Force Method (BNBC’93) and Response Spectrum
Analysis (Dynamic) using a comprehensive 3D finite element software
package ETABS v13.0
 To make a comparative study of the results obtained from the static and
dynamic analysis.

4.  In this study, a 3D symmetric model of a six-
storied building has been created using ETABS
V-13.0
 The structure has a constant stiffness and a
linear behavior of all material properties.
 Equivalent Static Force Method (BNBC’93) has
been used for static analysis.
 Response Spectrum Method has been used for
dynamic analysis.

5. Earthquake is a series of vibrations induced
in the earth’s crust by the abrupt rupture and
rebound of rocks in which elastic strain has
been slowly accumulating.
The release of the energy results in vibratory
waves propagating through the surface in all
directions.

6. Factors affecting the earthquake performance
of reinforced concrete structure:
 Ductility Capacity
 Effects of Drifts
 P-Delta effect
 Effects of strong Beams and weak
Columns

7. Static Analysis
Response
Spectrum Analysis
Time History
Method

8.  It assumes that the building responds in its
fundamental mode.
 The building must be low-rise and must not
twist significantly when the ground moves.
 Generally determines the shear acting due
to an earthquake as equivalent static base
shear.

9.  The basic mode superposition method.
 Restricted to linearly elastic analysis.
 Produces the complete time history
response of joint displacements and
member forces.
 Involves the calculation of only the
maximum values of the displacements and
member forces.

10.  It is an analysis of the dynamic response
of the structure at each increment of time,
when its base is subjected to a specific
ground motion time history.

11. Material Properties
Material Name Parameter Values Unit
Concrete
Mass per unit volume 4.662 lb-s2/ft4
Weight per unit volume 150 lb/ft3
Modulus of Elasticity 3604996.5 psi
Poisson’s ratio 0.2
Concrete compressive
strength,
3500 psi
Steel Steel yield strength, 60000 psi

12. Section ID Section Size (in×in)
Corner Column 12×12
Ext. Column 14×14
Int. Column 17×17
Beam 16×12
Grade Beam, GB 16×12
Section Properties
Slab Properties
Section name Thickness Type
Slab
Membrane: 5"
Bending: 5"
Shell

13. 3D View of the building

14. Beam Layout

15. Column Layout

16. Deformed Shape (Static)
Due to EQX Load

17. Deformed Shape (Dynamic)
Due to Response Spectrum

18. Mode Name Time Period Frequencies
Mode 1 2.436 0.41
Mode 2 2.34 0.42
Mode 3 2.29 0.43
Mode 4 0.704 1.42
Mode 5 0.679 1.47
Mode 6 0.657 1.52
Mode 7 0.374 2.67
Mode 8 0.359 2.78
Mode 9 0.351 2.84
Mode 10 0.245 4.08
Mode 11 0.233 4.29
Mode 12 0.231 4.32
Mode Shapes

19. Mode Shapes
Mode- 1 Mode- 2

20. Mode Shapes
Mode- 3 Mode- 4

21. Mode Shapes
Mode- 5 Mode- 6

22. Mode Shapes
Mode- 7 Mode- 8

23. Mode Shapes
Mode- 9 Mode- 10

24. Mode Shapes
Mode- 11 Mode- 12

25. Comparative Study
Storey Displacements

26. Comparative Study
Storey Drifts

27. Comparative Study
Maximum Storey Displacement

28. Comparative Study
Base Shears

29. Comparative Study
Shear Forces (Corner Columns)

30. Comparative Study
Shear Forces (Exterior Columns)

31. Comparative Study
Shear Forces (Interior Columns)

32. Comparative Study
Maximum Shear Forces

33. Comparative Study
Total Shear Forces

34. Comparative Study
Bending Moments (Corner Columns)

35. Comparative Study
Bending Moments (Exterior Columns)

36. Comparative Study
Bending Moments (Interior Columns)

37. Comparative Study
Maximum Column Bending Moments

38. • In the study of Maximum displacement of storey
comparison between static and dynamic, we find
dynamic is 276 percent of static analysis.
• In the study of Storey drift comparison between
static and dynamic, we find dynamic is 301 percent
of static analysis.
• In the study of Maximum Bending moment of
column, the percentage of dynamic is 204% for
corner, 239% for exterior, 210% for interior of
Static analysis.
• In the study of Maximum shear forces of columns,
dynamic is almost 286 percent of static analysis for
all columns.

39.  Dynamic analysis may be done by other methods.
 Structures of nonlinear materials may be
introduced for further analysis and design.
 Irregular shaped structure may be introduced for
further analysis and design.
 Dynamic analysis may be introduced for further
analysis and design.
 Commercial buildings may be introduced for
further analysis and design.

40. THANK YOU