Experimental and Theoretical Investigations of the Shear Resistance of SCS Composite Structures with Web Openings

Steel–concrete–steel (SCS) composite structures with continuous steel webs offer significant advantages in terms of structural capacity, waterproofness, construction efficiency, and others, and these structures constitute new options in large-scale subsea tunnel projects, nuclear structures, and offshore engineering. The shear performance of SCS structures is a critical design issue, and the presence of unavoidable opening configurations in steel webs magnifies this problem. Because of the lack of studies on the shear behavior of SCS structures with web openings, experimental and theoretical investigations were performed. Three-point shear tests were first conducted. The effects of the size and shape of web openings on the shear capacity were studied, and the failure modes, crack development, and load transfer mechanisms of these structures were analyzed in detail. On the basis of test observations, a theoretical method was proposed to account for the influence of web openings on SCS structures and to predict their shear resistance. Through comparisons with existing methods, the proposed theoretical approach can be used to quantify the effect of web openings on the shear capacity reasonably accurately, thereby providing guidance for engineering design practice.