Seismic performance of prefabricated beam-to-column joint with replaceable energy-dissipating steel hinge

This study presents a novel energy-dissipating prefabricated joint for connecting beam to column in a precast frame structure. The joints are characterized by a replaceable steel hinge and a prefabricated steel tube confined joint core, providing advantages for precast concrete reinforced frames, such as complete assembly, damage control, and maintainability of the structure after an earthquake. The hysteretic behavior of the proposed prefabricated joint was studied through two tests. First, a full-scale prefabricated joint was tested under cyclic loading until failure. On the basis of the initial test, only four weakened dissipaters of the steel hinges in the prefabricated joint were replaced and the second test was conducted to investigate the restorable functional characteristics of the proposed prefabricated joints. For comparison, a reference monolithic joint was also tested. The experimental results demonstrate that the novel prefabricated beam-to-column joint displayed excellent hysteretic performance, and corresponding to the monolithic joint, the load-bearing, energy dissipation, and deformation capacity were improved. The damage of the prefabricated joint was concentrated on the weakened dissipaters of the steel hinges, indicating that the failure mode and damage degree of the prefabricated joint can be controlled. In the second test, the prefabricated joint exhibited similar hysteretic behavior to that of the first test; however, the initial stiffness was slightly lower. Therefore, the prefabricated joint can meet the replaceability requirement and achieve satisfactory beam-to-column joint function recovery after an earthquake.