Evaluation of modal and FEMA pushover analyses: Vertically "regular" and irregular generic frames

The accuracies of the nonlinear static procedure (NSP) were evaluated using the modal pushover analysis (MPA) and lateral force distribution procedures. The median seismic demands were computed by these procedures for six SAC buildings, each analyzed for 20 ground motions, and compared with results obtained from nonlinear response history analysis (RHA). It was found that if a sufficient number of modes were included, the height-wise variation of story drifts determined by MPA was similar to the results from RHA. It was also found that MPA was almost always more accurate in estimating drifts in all stories of all frames than all of FEMA distributions.