Seismic performance of steel frames equipped with buckling-restrained braces (BRBs) using nonlinear static and dynamic analyses

Abstract

The current paper compares the seismic performance of buckling-restrained braced frames (BRBFs) and ordinary concentrically braced frames (CBFs) through nonlinear static and time history analysis. Two groups of BRBFs and CBFs including 5, 10 and 15 story frames are modeled and nonlinear pushover analysis is carried out. To further investigate the performance of frames, a selection of near-fault and far-field ground motion records are used for time history analysis. The results indicate the acceptable seismic performance and conformity of low-rise CBFs with BRB frames under far-field records. However, BRB frames present more satisfying results with regards to inter-story drifts, residual drift responses and energy dissipation in case of near-fault seismic excitations. Moreover, the implementation of BRBs provides better performance against the Basic Safety Earthquake 1 (BSE-1).