Seismic performance of high-rise buildings with energy-dissipation outriggers

Abstract

To improve the seismic performance of high-rise building structures with outriggers, a new structure with energy-dissipation outriggers installed using buckling restrained braces (BRBs), which replace the ordinary diagonal bracing, is proposed in this study. To verify the seismic performance of the new structure, a case study was carried out. Two high-rise structures, one with conventional outriggers, the other with energy-dissipation outriggers, were designed. The numerical models for the two structures were established with the aid of a commercial software, Perform-3D. The responses of the two structures under frequent earthquakes, basic earthquakes, and rare earthquakes were analyzed and compared. The results show that compared to the ordinary structure, the seismic performance of the new structure is improved significantly. Under frequent earthquakes, both structures remain basically elastic, and the responses of the two structures are almost identical. Under basic earthquakes and rare earthquakes, the BRBs in the new structure yield initially and dissipate a large amount of the input energy to provide adequate protection to the main structural members. Furthermore, the influences of the strength and layout of BRBs on the seismic performance of the new structure were investigated, providing reference for engineering applications.