Seismic Performance Evaluation of RC Buildings with Regular And Irregular Floor Masses

Authors

  • G. Suresh  P. G. Student, Department of Civil Engineering, Sir Vishveshwaraiah Institute of Science and Technology, Madanapalle, Andhra Pradesh, India
  • R. Arun  Asst. Professor, Department of Civil Engineering, Sir Vishveshwaraiah Institute of Science and Technology, Madanapalle, Andhra Pradesh, India

Keywords:

Heavy Mass, Heavy Machinery, Seismic Evaluation, Mass Irregular Buildings.

Abstract

Mass irregularity is the presence of heavy mass on a floor or when one floor is much heavier than the others, e.g., heavy machinery or a swimming pool installed on an intermediate floor of a building. In this study the slab thickness i.e., floor mass is varying. Slab thickness is increased at alternative floors in mass irregular buildings. 0.15 m slab thickness is taken for the without mass irregular buildings and for mass irregular buildings slab thickness is taken as 0.30m.In light of these facts, it is imperative to seismically evaluate building with the present day knowledge to avoid the major destruction in the future earthquakes.

 

The dissertation work is concerned with the comparison of the seismic evaluation of RC buildings with and without mass irregularity, the method carried out in terms of equivalent static, response spectrum and pushover analysis according to IS 1893:2002(part1) code.G+2 to G+8 storey buildings are considered for the analysis. In this analysis for mass irregular buildings, the floor mass is varied at 2nd, 4th, 6th, 8th floor of all the buildings. The comparison of equivalent static response spectrum method and pushover analysis by using finite element software package SAP2000 version 14.0.0 is used to perform the modeling and analysis of G+2 to G+8 storey’s buildings by considering the seismic zone V as per IS 1893:2002(part 1) code. For analysis various IS codes have been referred. For Gravity load combination IS 456:2000 and for 0.9, 1.2 and 1.5 seismic load combinations as per IS 1893:2002 (part 1) code is referred. In this study building model analysis carried out namely gravity, equivalent static, response spectrum & pushover analysis in longitudinal direction & transverse direction discussed and comparisons of codal values of the software analysis values. Results of these analyses are discussed in terms of the time period, storey displacement, storey drift and base shear. From this results it is concluded that time period, storey displacement, storey drift and base shear will be more in mass irregular buildings compare with the without mass irregular buildings.

References

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Published

2017-02-28

Issue

Section

Research Articles

How to Cite

[1]
G. Suresh, R. Arun, " Seismic Performance Evaluation of RC Buildings with Regular And Irregular Floor Masses, International Journal of Scientific Research in Science and Technology(IJSRST), Online ISSN : 2395-602X, Print ISSN : 2395-6011, Volume 3, Issue 1, pp.308-314 , January-February-2017.