Displacement based seismic design of high rise buildings with strengthened stories

A displacement based seismic design method for high-rise building with strengthened stories is put forward combined with finite element modal analysis. Considering the mechanical and deforming characteristic of high-rise buildings with strengthened stories, the stories above the strengthened ones are taken as the key stories. The performance objects of the building under lateral loads are determined by the performance of the key stories. Modal pushover analysis is adopted in the displacement based seismic design in which the contributions of higher modes are combined using SRSS rule to consider their effects. To verify the feasibility of the design procedure proposed, a 52-story high rise frame-tube building with strengthened stories is taken as the modal building. Modal pushover analysis is performed on this modal building and the proposed design procedure is applied to it. The design results show that the proposed displacement based seismic design procedure is applicable and effective and is valuable for the actual design of high rise buildings with strengthened stories.