Behavior Factor of RCMRFs Based on Incremental Dynamic Analysis

The seismic codes usually extract the design forces by using a behaviour factor that modifies the ‘linear’ force system to an equivalent one to account approximately for the nonlinear effects. The issue of the behavior factor is of great interest in earthquake-resistant design, as the design forces are inversely proportional to the value adopted for this parameter. The factor that reflects the capability of a structure to dissipate energy through inelastic behavior is the ratio of the strength required to maintain the structure elastic to the inelastic design strength of the structure. The objective of this study is to determine the behavior factor of Reinforced Concrete Moment Resisting Frames (RCMRFs) by employing nonlinear incremental dynamic analysis. First, several sample frames are selected and designed based on the ACI regulations. Then nonlinear incremental dynamic analysis is performed on the structures and the behavior factors are determined. The results are compared with those from pushover analyses. It is shown that the behavior factors resulting from the nonlinear incremental dynamic analysis are generally larger than those obtained from pushover analysis and were similar to the values given in the design code

Keywords:

Reinforced Concrete Moment Resisting Frames , Incremental Dynamic Analysis , Behavior Factor