MODAL AND CYCLIC PUSHOVER ANALYSIS FOR SEISMIC PERFORMANCE EVALUATION OF BUCKLING-RESTRAINED BRACED STEEL FRAME

摘要

Buckling-Restrained Braces (BRBs) are confirmed to have nearly the same yielding stress and ultimate strength under tension and compression. The BRBs can undergo fully-reversed axial yield cycles without loss of stiffness and strength, whose seismic energy dissipation ability is superior. Based on modal pushover analysis, the influence of higher vibration modes of Buckling-Restrained Braced steel frame was considered. Compared to non-linear static procedure, the results of modal pushover analysis agree better with that of nonlinear response history analyses. Based on cyclic pushover analysis, the hysteretic behavior of Buckling-Restrained Braced Steel Frame (BRBSF) was researched. After installed with BRBs, the energy dissipation of BRBSF is completed by the hysteretic deformation of BRBs, the seismic responses of the structure will be greatly reduced and seismic performance will be improved.