Seismic performance of T-shaped precast concrete superposed shear walls with cast-in-place boundary columns and special boundary elements

Abstract

The seismic behaviors of three full-scale T-shaped precast concrete superposed shear wall specimens with cast-in-place boundary columns and special boundary elements and two those of T-shaped cast-in-place shear wall specimens for reference were investigated using quasi-static cyclic loading test. In this study, a novel vertical joint of superposed wall panels and special boundary elements was designed differently from that obtained using additional overlapped connecting steel bars. The failure mode, strength, hysteresis feature, ductility, energy dissipation capacity and stiffness degradation of each specimen were compared. The influence of different connecting methods of vertical joint, boundary elements and axial compression load ratios on the seismic behavior of T-shaped superposed shear walls were analyzed. The test results show that the T-shaped superposed shear walls with boundary columns and an axial compression load ratio of 0.2 exhibited seismic performances close to that of the reference T-shaped cast-in-place shear wall, and the T-shaped superposed shear walls with special boundary elements and an axial compression load ratio of 0.4 exhibited seismic performances equivalent or even superior to that of the reference cast-in-place specimen in the loading direction along the web axis. The T-shaped superposed precast concrete shear wall specimen with the new connecting method of vertical joint exhibited higher strengths, deformation capacities and energy dissipation capacities than that of the T-shaped superposed precast concrete shear wall specimen with the traditional overlapped connecting method. Furthermore, the shear strength of all the specimens calculated by the formulas recommended in the Chinese code JGJ 3–2010 were smaller than the tested peak load.