Experimental study on seismic performance of precast concrete composite #br#
shear walls embedded with high-strength concrete-filled double steel tube
Xiong Feng1 Huang Yansheng1 Zhou Jing1,2 Bu Guobin3
1. State Key Laboratory of Subtropical Architecture Science, South China University of Technology, Guangzhou 510640, China;
2. Xiangtan University, Xiangtan 411105, China; 3. Hunan University of Technology, Zhuzhou 412007, China
Abstract:A kind of precast concrete composite shear wall embedded with high-strength concrete-filled double steel tubes is proposed, which is suited for use in the high-rise buildings. The seismic performance and damage mechanism, assembly integrity of the precast composite walls were studied through the quasi-static tests of two-storey composite wall specimens with a shear-span ratio of 2.86. The results indicate that the specimens fail in a flexural-shear coupling mode, characterized by the tensile yield of vertical reinforcements and boundary steel tubes, the compressive crushing of concrete and the local buckling of boundary steel tubes at the wall bottom of first storey. Cracks developed and distributed in both the post-cast concrete and the precast concrete, but there was no inplane slide between the precast wall and the post-cast connection part. The hysteresis curves had obvious pinched phenomenon, and the skeleton curves normally had a gentle decline stage after the peak load, which demonstrate considerable plastic deformation and ductility and good assembly integrity of the precast composite walls. Only the radial bolts can consolidate the inner steel tube and outer steel tube to achieve the constraints and connections. The offplane eccentric pressure has important influence on the hysteresis performance. The specimen subjected to a larger eccentric pressure still has better deformation and ductility capacity, indicating that the concrete-filled steel tubes enclosed into the assembly composite wall can reliably fulfill the connection function and improve the out-of-plane bending capacity. The specimen with small sectional content ratio of the concrete-filled steel tubes still has better displacement ductility, which implies that the parameters of the precast composite walls still need to be optimized.