FORCE/TORQUE PUSHOVER METHOD FOR PLAN IRREGULAR STRUCTURES

In the present study, a new pushover procedure for seismic static analysis of plan irregular 3D frame structures is proposed, based on the application of a set of horizontal force and torque distributions at each floor level. In order to predict the most severe configurations of an irregular structure subjected to an earthquake, more than one pushover analysis has to be performed. The proposed method is validated by a consistent comparison of results from static pushover and dynamic simulations in terms of different response parameters, such as displacements, rotations, floor shears and floor torques. Starting from the linear analysis, the procedure is subsequently extended to the nonlinear case. The results confirm that, in order to predict the structural behaviour in the most severe configurations, different force distributions must be defined.