Displacement-Based Seismic Design For HPC Shear Wall

Application of performance-based seismic design method has become an important research subject in international earthquake engineering. Reinforced concrete shear wall is a common member of resisting horizontal force in building structure. High strength concrete to be used in high or super-high building has much advantage. Because of brittleness and weakness of deformability, it should be studied how to improve the ductility capacity of HPC shear wall. The following work had been done about this:(1) In order to improve the deformability of the members, four specimens of high performance concrete shear wall, with parted confining stirrup at the potential plastic region, were designed and the quasi-static test had been carried out according to performance-based seismic design theory. By analysis of test, the influence of the axial compression ratio, the amount and range of confinement reinforcement on the ductility, the capacity of energy dissipation and failure behavior was analyzed. The amount and range of parted confining stirrup determined by the axial compression ratio and displacement ductility demand was demonstrated to be valid, and the ductility level of the high performance concrete shear wall met the demands of design.(2) A method to calculate the section curvature ductility index of high strength concrete shear wall is induced by using stress-strain relationship of rectangle stirrup and plane section assumption. By using theoretical calculation, the relationship of boundary constrain extend and axial compression ratio with shear wall deformability is studied. Based on test and theory, a method is developed how to arrange confinement reinforcement in boundary member to meet deformability demand.The comparison between test results and theoretical results indicated that the calculation method of shear wall section curvature ductility index is reliable and effective. Shear wall confinement reinforcement can be designed to meet the ductility ability demand through theoretical calculation by this way.