Experimental investigation and strength evaluation of steel-plate composite wall-to-wall L- and T-joints with different novel shear reinforcement

Abstract

The steel-plate composite wall-to-wall joint configuration specified in current design codes is particularly susceptible to shear failure. Existing experimental studies have reached contradictory conclusions regarding whether shear reinforcement can enhance joint strength. The influence of shear reinforcement on joint behavior has not yet been fully understood and quantified. The reinforcement types need to be developed to better align with the concept of industrialized prefabricated construction. This paper makes a contribution toward addressing these gaps. First, based on the authors’ previous theoretical findings, three novel and practical shear reinforcement configurations were proposed according to three distinct mechanisms, including cross, annular and UHPC reinforcement. On this basis, considering different shear reinforcement ratios and joint external constraints ( L -joint and T-joint), a hysteretic test matrix consisting of 9 specimens was established. The test results indicate that the proposed shear reinforcement can improve joint performance, with the extent of improvement governed by the reinforcement configuration, the reinforcement ratio, the joint external constraints, and the strength ratio between the unreinforced joint and the wall. Finally, to quantify the test results, the analytical strength model previously proposed by the authors for L -joints with rebar cage shear reinforcement was extended to both L- and T-joints with all available types of shear reinforcement, yielding a standard deviation of the predicted strength ratio that is 68% lower than that of AISC N690.