Experimental Study on the Seismic Behavior of Squat SRC Shear Walls with High Axial Load Ratio

Abstract

This paper aims to study the seismic behavior of squat steel-reinforced concrete (SRC) shear walls with a high axial load ratio. Nine squat SRC shear walls with varying axial load ratios, steel ratios, and horizontal distributed reinforcement ratios were tested under lateral cyclic reversed loading and an axial load. The failure process, load-deformation hysteretic response, shear strength, ductility, and the strain of the specimens are reported. The results show that all the specimens failed in shear with the crushing of the web concrete. No axial failure occurred after the web concrete was crushed since the boundary elements encased with structural steel sections maintained the axial load. Larger steel ratios reduced the buckling degree of the structural steel. A larger horizontal distributed reinforcement ratio was clearly beneficial for the ductility and energy dissipation capacity of the specimen, while it had a negligible effect on the shear strength. The Chinese code provided an extremely conservative prediction of the shear strength of the tested squat SRC shear walls with a mean calculated-experimental strength ratio of 0.42. An improved formula was established mainly by the modification of the shear resistance contributed by the concrete and the structural steel, leading to a mean calculated-experimental strength ratio of 0.74. More experimental data are still needed to establish more accurate deformation acceptance criteria for SRC shear walls and to promote the performance-based seismic evaluation of SRC structures.