Effect of Modeling on Time Period & Lateral Load Estimation of R.C.C. Buildings

Abstract

Conventionally, seismic design of building structures is based on the concept of increasing the resistance capacity of the structures against earthquakes by employing, Shear walls, Braced frames or MR frames. However, the periods of vibrations of above mentioned structures are primary tools in determining seismic response. The period of vibration of structures is highly varied in nature depending upon its determination approach. This paper is an attempt to focus the issue of variation of time period determination from empirical formulas to software model implementation. In this paper a small R.C.C. Building of G + 4 size has been taken and different modeling aspects were applied to evaluate the difference in time period of the building. Based on the evaluated time periods the equivalent static lateral loads on the building were also estimated and distributed along the height of the building. The software used to model the R.C.C. building is ETABS Nonlinear Version 8.11. Lastly, a comparison of time periods for different types of model and base shear were also obtained. Overall, the paper is a modest attempt to bring in front the basic issues of obtaining time period for correct evaluation of seismic response of R.C.C. buildings, which felt missing.