Seismic performance of precast concrete shear walls with spiral stirrup restrained grout-anchored lapped reinforcement connection

Low-cycle reversed loading tests and finite element analysis were conducted on one cast-in-place (CIP) shear wall specimen and two precast concrete (PC) shear wall specimens with different configurations of spiral stirrup. By comparing the failure modes, load-carrying capacities, hysteresis behaviours, skeleton curves, deformation capacities, stiffness degradation, plastic hinge distributions, and energy dissipation capacities of the PC specimen and the PIC specimen, the mechanical properties of the PC specimen equivalent to those of the CIP specimen were verified. Both the PC and PIC specimens exhibited bending shear failure, consistent with the ductile failure design requirements of "equivalent to cast-in-place". The peak load capacity of the PC specimen was 3.64% higher than that of the PIC specimen, and the hysteresis curve was as full as that of the CIP specimen. The stiffness degradation performance of the PC specimen was slightly lower than that of the CIP specimen in the cracking stage, but it was comparable to that of the CIP specimen after entering the elastic-plastic stage. During the yielding stage, the maximum difference in energy dissipation performance between the CP specimen and the CIP specimen did not exceed 11.34%. Both the tests and finite element analysis confirmed the effective constraint of spiral stirrup on lap joints. Setting spiral stirrup for the vertical distribution reinforcements on the web had no significant effect on the load-carrying capacity of the PC specimen, but it slightly reduced its ductility and energy dissipation performance, by no more than 6.63%. For economic and safety considerations, it is not recommended to use spiral stirrup in this area.