Axial compression behavior of corrugated steel-concrete composite arches

The corrugated steel-concrete composite (CSCC) arch is characterized by high stiffness, good ductility, showing promising application prospects in bridge and tunnel structures. In bridge and tunnel engineering, arch structures are primarily subjected to combined axial and bending loads. Among these, axial compression behavior plays a fundamental role and serves as the basis for understanding and evaluating their compressive-bending behavior. However, few studies have focused on the axial compression capacity of CSCC arches, and their load-bearing mechanisms and failure modes remain unclear. To address the above issues, experiments and finite element (FE) analyses were conducted on the CSCC arch. First, tests on three CSCC arches with a span of 6 m and varying concrete thicknesses, along with one RC arch as a comparison specimen, were conducted. After that, a refined numerical model of the CSCC arch was developed and validated, and a parametric analysis was conducted to identify the influence of key parameters on the axial compression capacity. It was found that compared to the RC arch with the same steel ratio, the CSCC arch exhibited 15.2 % higher ultimate resistance and 21.9 % greater initial stiffness, demonstrating its superior mechanical performance. Compared to the corrugation size of corrugated steel (CS) 125 mm × 25 mm, the corrugation size 400 mm × 150 mm exhibits an 8.3 %–17.7 % increase in axial compression capacity of the CSCC arch. Finally, a design method is proposed to predict the axial compression capacity of the CSCC arch.