Experimental and Numerical Study on Seismic Behavior of High-strength Concrete Shear Walls Confined by High-Strength Spiral Stirrups

Abstract

In recent years, with the continuous increase in building height, the shear walls at the bottom of high-rise structures are subjected to increasingly large vertical loads. Under strong seismic actions, high-strength concrete shear walls with high axial compression ratios are prone to brittle failure, while the end hooks of stirrups tend to open, resulting in a loss of confinement effect on the concrete and longitudinal reinforcement. Studies have shown that the use of high-strength spiral stirrups in concrete columns can effectively confine the core concrete and longitudinal reinforcement, avoiding the opening of end hooks in conventional monolithic hoops. This not only improves the seismic performance of columns but also saves steel and enhances construction efficiency. To enhance the ductility of shear walls, this study applies high-strength spiral stirrups to shear wall structures and investigates their seismic performance through low-cycle reversed loading tests. The experimental results demonstrate that the use of high-strength spiral stirrups significantly improves the ductility and energy dissipation capacity of shear walls, while delaying stiffness degradation. Based on these findings, a restoring force model suitable for such components is established, providing a theoretical basis for the seismic design of high-rise structures.