Experimental study on corrugated steel-concrete composite semicircular arches under midspan loading

Corrugated steel-concrete composite arch is a novel structural form that increases the load-bearing capacity of corrugated steel (CS). In this study, the static performance of a CS-plain concrete (CSPC) semicircular arch and CS-reinforced concrete (CSRC) semicircular arch was experimentally investigated under midspan loading using six arch specimens. The performance of four CSPC arch specimens with different bond strengths and concrete strengths was tested and compared. The results showed that insufficient bond strength between CS and concrete caused concrete breakout failure and affected the ultimate bearing capacity significantly, with the largest reduction of 62%. Therefore, adopting a high concrete strength can significantly improve the concrete cracking load and bearing capacity of CSPC arches. Subsequently, a CSRC arch was also tested, together with a reinforced concrete (RC) arch, to investigate the failure mode and ultimate bearing capacity. It was found that because of the high moment of inertia and contribution of the CS to the shear strength, the stiffness and ultimate bearing capacity of the CSRC arch were higher by 86% and 90%, respectively, than that of the RC arch with the same amount of concrete and steel. In addition, based on the measured strain, composite and confining effects were observed in the CSRC arch; however, the confining effect was negligible.