Seismic Performance Evaluation of RC Buildings Using Irregularity Based Indices

Abstract

Earthquakes may cause structural and non-structural severefig damage and failure during seismic excitations. These collapses and damages start from the weak points of the structures. The reason for these weak points in structures is the mass, rigidity, and discontinuity in the geometry of the structure. These vertical irregularities are one of the major reasons for the failure of structures during earthquakes. Fifteen models are considered in this project to examine the behavior of the building with different heights and vertical irregularities. The seismic response of these selected setback frame structures have been compared with regular frame structures using finite element method-based software SAP2000 v22. In this work regular and setback models of 5 storey, 9 storey, and 13 storey RC frames are considered for modal and dynamic analysis by considering earthquake loads. Furthermore, irregularities indexes comparisons are carried out and discussed in detail for models. The methods used for the analysis are the static method and time history method.

Keywords

• discontinuity
• R/C building
• setbacks
• time history analysis
• vertical irregularity