For analyzing the complex behavior of reinforced concrete structures, nonlinear analysis has become an inevitable tool. In addition, this nonlinear analysis helps engineers to understand more about the behavior of structures during major earthquakes. Pushover analysis is a simple approximate nonlinear analysis which is used to analyze structures. In pushover analysis, the main objective is to obtain load versus deformation behavior for increasing lateral loads. We obtain the pushover curve or capacity curve which gives a rough estimate about lateral strength, stiffness and drift of structure. Structure capacity is described by pushover curve which is obtained from base shear versus roof displacement. In this paper, pushover analysis is done for different structures using SAP 2000, and the variation in structure is based on the symmetry of the structure.

If a structure is subjected to an earthquake, it shows inelastic deformation which can be accurately analyzed by nonlinear analysis techniques. Pushover analysis of structures determines the pushover curve, which is a curve between base shear and roof displacement. In addition, it produces the capacity spectrum which is a plot between the spectral acceleration and spectral displacement (Anil and Rakesh, 2002). Performance point is an important parameter in pushover analysis. It is the point where the capacity spectrum crosses demand spectrum. If this point exists within the safe limits, then the structure will perform better under seismic conditions.

Pushover analysis can be done either by displacement control or by force control and in this paper, it is done based on the displacement control (Rahul et al., 2004). Pushover analysis provides the sequence of yielding and failure of a member (Yue and Shaing-Yung, 2007). Pushover analysis option allows engineers to perform pushover analysis as per FEMA-356 and ATC-40.

Structural Engineering Journal,Pushover analysis, Base shear, Roof displacement, SAP 2000