Seismic performance of composite joints between prefabricated steel-reinforced concrete columns and steel beams: experimental study

The joint between beam and column is the crucial zone, which makes the study of seismic performance of fabricated frame structures difficult and challenging. Reliable connection of prefabricated steel-reinforced concrete (SRC) columns with steel beams by a simple and effective dry connection method is a very important technical problem. In view of this, a new type of modular prefabricated SRC column-steel beam composite joint (MPCJ) was developed in this study. Further, the quasi-static test was carried out on three different types of beam-column joints (i.e. bolted-welded hybrid connection, welding connection, and bolted connection), and the failure characteristics, hysteretic behaviour, strain law, ductility, energy dissipation capacity, strength, and stiffness degradation of the new MPCJ under low-cycle reciprocating loads were recorded and analyzed. The results showed that the failure mode of three MPCJ specimens was bending failure at the end of the beam; the MPCJs exhibited stable hysteretic curves, strength deterioration, and stiffness degradation; the ductility coefficients and the equivalent viscous damping coefficients of the three specimens were found to be greater than 4 and 0.2, respectively, which meet the requirements of seismic performance limits. In summary, the new MPCJ has the advantages including large bearing capacity, high construction efficiency, energy saving, and environmental protection. It has important theoretical and practical value for future in-depth study of assembled SRC composite frame structure.