Seismic performance and post-earthquake function recovery of prefabricated reinforced concrete (RC) beam-column joints

The concept of structural recoverability has emerged as a crucial performance objective in the seismic design of structures. This paper introduces a novel replaceable prefabricated RC beam-column composite energy dissipation joint, which primarily consists of composite energy-dissipation boxes (EDBs) and friction side plates (FSPs). A total of three specimens were fabricated, and low-cycle reciprocating tests were conducted to investigate their failure modes, hysteresis performance, strength degradation, and displacement ductility. The results indicated that all specimens exhibited ductile failure modes, characterized by the formation of plastic hinges at the beam ends of cast-in-place joints, alongside damage to the FSPs and composite EDBs in the prefabricated joints. The prefabricated specimen demonstrated strong displacement ductility and rotational capacity. Following the replacement of the composite EDBs, the repaired specimen exhibited a 7.75 % reduction in peak bearing capacity due to damage to the FSPs. However, its displacement ductility and energy dissipation capacity were less affected, suggesting that the proposed new energy-dissipating joint possesses robust seismic performance and facilitates functional recovery post-earthquake.