Experimental research on the seismic and repair performance of steel beam-column joint with replaceable bio-inspired hinge

A novel steel beam-column joint with a replaceable bio-inspired hinge (RBHJ) was developed to simplify the prefabricated beam-column joint structure in this paper. The replaceable bio-inspired hinge (RBH) consists of a connection system providing rotational capacity and an energy dissipation system offering flexural capacity. To evaluate the seismic performance and repairability, three RBHJ specimens were designed to conduct the three hysteretic and three remediation experiments. The influence parameters (whether to add rubber, the diameters of the curved panels, and the thicknesses of the energy dissipation plates) on the RBHJ performance in terms of failure process and modes, hysteretic and skeleton curves, ductility coefficient, and energy dissipation behavior were explored. It was found that the RBHJ damages emerged at the weakening location of the energy dissipation plates, and there was no visible deformation observed in other components. The RBHJ specimen still exhibited a stable hysteresis curve after three repeated repairs. The hysteresis curve of RBHJ exhibited a complete shuttle-like form, with its peak viscous damping ratio attaining 38.14 %. The maximum interlayer displacement angle of the RBHJ reached 8.70 %, and the ductility coefficient of all specimens exceeded 3 except for the specimen D270-T10-W30-R. Based on the working mechanism and mechanical model, a corresponding formula for calculating the yield flexural bearing capacity of the RBH was derived.