Seismic performance of a two-level yielding rocking steel frame
Wang Hanqin1 Feng Yulong1,2 Jiang Qing1,2 Chong Xun1,2
1. School of Civil Engineering, Hefei University of Technology, Hefei 230009, China;
2. Anhui Civil Engineering Structures and Materials Laboratory, Hefei University of Technology, Hefei 230009, China
Abstract:A two-level yielding rocking steel frame with buckling-restrained columns (TYRSFB) was proposed to enhance the stiffness and carrying capacity of rocking steel frame (RSFB) after buckling-restrained column (BRC) yielding, which is constructed by adding a steel rod at each side of BRC in RSFB. To realize only tension in steel rod and structural two-level yielding, the pinned connection and a restrainer were used to connect the bottom of steel rod with foundation and the top of steel rod with the short beam in rocking steel frame, respectively, and a certain gap was set between the restrainer and short beam. The pseudo-static tests and simulations were conducted on the TYRSFB and RSFB, and results indicate that although the performance of test specimens cannot be fully used due to the failure of out-of-plane restraints in pseudo-static tests, the test specimens have excellent deformation controlling capacity, and rocking steel frames remain elastic. The proposed connection configuration of steel rod can realize only tension in steel rod and structural two-level yielding. Before the steel rod working, the performance of TYRSFB is basically same as the RSFB. After the steel rod joining, the stiffness and carrying capacity of TYRSFB are significantly higher than those of RSFB. Meanwhile, the addition of steel rods has little influence on the performance of BRCs.