Mechanism and seismic performance of a novel precast concrete beam-to-very short shear link joint: Experimental and numerical simulation

This paper introduced a novel precast concrete beam-to-very short shear link (PCB-VSSL) joint with the separation from shear force and bearing moment. The mechanism and seismic performance of the PCB-VSSL joint were detailed investigated. In the present study, four specimens were investigated by cyclic loading tests, including a very short shear link-1 (VSSL-1), a novel joint with basic shear connectors (PCB-VSSL-1), and two improved joints (PCB-VSSL-2 and 3), and the influencing factors including the length of cross-bilinear-type (CBT) shear connector and lateral plate height in the CBT shear connector were analyzed by experimental and numerical simulation. The test results showed that the PCB-VSSLs had excellent bearing capacity and energy dissipation capacity, and maximum overstrength and inelastic rotation of VSSLs in the specimens PCB-VSSL-1, 2, and 3 were 1.85 and 0.15, respectively, which were the same as the specimen VSSL-1. The concrete cracks of the precast concrete beam could be minimized by enlarging the length and area of shear connectors. The results also indicated that the high-strength bolts would only transfer the bending moment from the VSSL to PCB-VSSL. The shear connectors only sustained the shear force, so the bending moment and the shear force of the novel PCB-VSSL could be effectively separated with the advantage of high bearing capacity, reasonable mechanics, ease of installation, and seismic resilience capacity. Furthermore, based on the finding of on failure mechanism of the PCB-VSSL joint, a simplified design methodology of the novel PCB-VSSL joint was proposed.