Seismic loss comparison for buildings designed with ductile steel seismic force‐resisting systems and with controlled rocking braced frames

Observations from past earthquakes have highlighted the structural damage and significant residual deformations experienced by ductile steel seismic force‐resisting systems (SFRSs), such as special moment resisting frames (SMRFs), special concentrically braced frames (SCBFs), and buckling‐restrained braced frames (BRBFs). To mitigate these challenges, controlled rocking braced frames (CRBFs) have emerged as a promising low‐damage alternative SFRS. However, concerns have been raised about whether the reduction in structural damage with CRBFs may come at the cost of increased acceleration demands and associated nonstructural damage. This study offers a comprehensive investigation of such trade‐offs by analyzing three buildings of different heights, each designed with the three ductile SFRSs identified above and with CRBFs. After examining the structural response at different earthquake intensities, the focus of the paper is on earthquake‐induced economic losses. Among the considered SFRSs, greater total expected annual losses (EAL) are observed in the SMRF and SCBF buildings, primarily due to demolition losses and repairable losses, including repairs of structural and nonstructural components. The total EAL is lower for the BRBFs and lowest for the CRBFs, with the losses in the BRBF buildings primarily attributed to demolition loss, considered as irreparable loss, while the losses in the CRBF buildings are mainly due to acceleration‐sensitive nonstructural components, considered as reparable loss. To provide a more detailed comparison, cost‐effectiveness analyses are also performed, indicating that a modest cost premium for CRBFs is justified to reduce earthquake economic costs over the building lifetime.