Seismic performance of a new type of RC shear walls confined with high-strength rectangular spiral reinforcements

To improve the seismic performance of structures, a new type of reinforced concrete (RC) shear walls confined with high-strength rectangular spiral reinforcements (HRSRs) is proposed. Pseudo-static tests were conducted on four 1/2-scale HRSR shear walls possessing different parameters. The influence of HRSR on the lateral-load capacity, ductility, and failure modes of the shear walls was systematically studied. The test results clearly indicate that using HRSR as hoops and transverse reinforcements can effectively restrain the deformation and capacity-decline stage of the high-strength concrete shear walls, improving their lateral-load capacity and ductility. Particularly, the seismic performance of the RC shear walls with a high axial-compression ratio can be significantly improved by applying HRSR. A simplified model was proposed for the ultimate flexural capacity of the HRSR shear walls, which precisely agreed with the experimental results. These results provide a new strategy for seismic-performance design of RC shear walls in engineering structures.