Seismic performance evaluation for a vertical irregular structure

Based on the modal pushover analysis (MPA) and the constant-strength ductility demand spectrum method, the basic solving process of a vertical irregular structure was put forward. Using the modal pushover analysis, the influence of higher modes could be taken into account. Using the constant-strength ductility demand spectrum method, the ductility and displacement demand of the equivalent single degree of freedom system were obtained, then they were translated into the displacement demand of a multi-degree of freedom system. Using these methods the examples of typical irregular vertical structures were analyzed, the results demonstrated that these methods could be used in the seismic performance calculation of a vertical irregular structure effectively.