Performance-based seismic design of laterally braced steel frames

Improving the performance of structural frames is one of the most important focuses of today's researchers. The total base shear capacity of the structural frames will increase by reaching the maximum number of plastic hinges. In this work, the effects of bracing system type on different heights of steel frames were investigated. Static pushover analysis was used to evaluate the performance of 4, 8, and 12-story steel frames with seven structural configuration systems. The results showed that the performance of braced frames increased significantly in terms of number of plastic hinges, total base shear and performance point compared to unbraced frames. The capacity curves were maximum in the one-story X-bracing, multi-story X-bracing, and single diagonal bracing systems.