Seismic behavior of CFST components for shear walls using double corrugated steel plates

The corrugated steel plate (CSP) demonstrates satisfactory energy-dissipating performance when utilized in shear walls due to its higher out-of-plane stiffness and local buckling resistance. Based on this, a composite shear wall incorporating multiple pure horizontal CSPs and concrete-filled steel tube (CFST) components was proposed. The CFST components are fabricated by welding double horizontal CSPs and double flat steel plates (FSPs) together, and then infilled with concrete. As the load-bearing component in the hierarchical seismic system, the CFST components with double CSPs have exhibited satisfactory bearing performance. Therefore, this study investigates the seismic performance of the CFST component using double CSPs through quasi-static tests on seven specimens. All specimens experienced plastic buckling failure of the FSPs at the crest section near the component foot, with the CSPs effectively confining the core concrete. Despite the CSPs having a width-to-thickness ratio significantly exceeding the limits for flat plates specified in design codes, reaching up to 325.3, all specimens achieved ductility coefficients greater than 3.0, demonstrating satisfactory seismic performance. Compared with the adjustment of CSP thickness and vertical reinforcement, the bearing capacity was significantly increased by 37.6 % with a 50 % increase in FSP thickness. The increase in the section aspect ratio from 1 to 1.5 and 2 resulted in peak load increases of 62.9% and 167.3%, respectively. Meanwhile, the load-carrying capacity under weak axial loading is 37.9% lower than that under strong axial loading. Additionally, the stiffness degradation, ductility, strain response, and energy dissipation under each parameter were systematically investigated. The proposed compression-flexural capacity model predicts the test results well, with an average ratio of predicted values to experimental load capacity of 0.97 and a variance of 0.06. This study provides valuable guidance for the design of composite shear walls using CSPs.