Experimental Study on Seismic Behavior of a new fully precast rocking beam-column joint

Abstract

A new fully precast replaceable energy dissipation rocking beam-column joint (RBCJ), formed by adopting the splice joint and connecting through energy-dissipating steel plates, was proposed via referring to the mortise-tenon work in Chinese ancient architectures, aiming to improve the repairable performance of reinforced concrete (RC) joints after strong earthquakes, reduce the residual deformation of the structure and realize the rapid recovery of building functions after earthquakes. Two one-half scale beam-column joints with different lap lengths were designed and fabricated. Unidirectional low-cycle reciprocating loading of the specimen by quasi-static test, the failure process, and the influence of lap length of the splice joint on the seismic performance of the specimen were studied, and the hysteresis tests was carried out on the repaired specimen again to study the repairable performance of the RBCJ. The research showed that the residual displacement of the specimen was small, and the plastic deformation was concentrated on the replaceable energy-dissipating parts. The concrete at the edge of the dapped-end part in the long-lap-RBCJ-connecting specimen was slightly cracked, and there was no serious damage in other areas of the prefabricated member. The short-lap specimen had better seismic performance than the long-lap one. After the loading drift of the short-lap specimen reached 1 /50, the repair work was completed by replacing energy-dissipating connecting steel plates, and the seismic performance of the repaired joint had not decreased significantly. To facilitate engineering application, the equations of yield load and ultimate load that joint can undergo were deduced according to thin plate theory, the relationship between ultimate bearing capacity and thickness of energy-dissipating steel plates was given, and local stress and failure mechanism of the splice joint were analyzed, and shear and pull-out checking calculations of bolts were carried out.