Seismic behavior of chevron braced reinforced concrete spatial frame

Bracing system is one of the most effective systems to improve the seismic performance of reinforced concrete (RC) plane frames; however, the guidelines for its use in RC spatial frames (RCSFs) still require improvement. The effectiveness of braces utilized in RCSFs was investigated in this study. Cyclic tests of three ¼-scale RCSFs were conducted to assess the seismic performance of an RC-braced spatial frame. Test results indicate that RCSFs with braces exhibit better performance than normal RCSFs in terms of strength, stiffness degradation, hysteresis loop, and energy dissipation. RCSFs with braces also exhibit an overall failure mechanism rather than the inter-storey mechanism exhibited by normal RCSFs; such mechanism is significant in the seismic design of RCSFs. After brace failure, braced RCSFs can continue to bear loads in a similar manner as normal RCSFs; this condition reveals the redundancy of braced RCSFs. Overall, braced RCSF has better seismic performance than normal RCSF.