Experimental investigations of beam-column joints with replaceable BRFCPs using sliding restraint plates

This paper proposes a replaceable buckling-restrained flange cover plate (BRFCP) for steel beam-column joints with cantilever beam segments, in which a sliding restraint plate (SRP) with slotted holes is used to constrain the core plate buckling deformation and simultaneously control the restraint plate without significant damage. First, theoretical analyses and design considerations were presented for this joint. Second, cyclic loading tests were conducted on five joints with different BRFCP configurations, including different formats of restraint plates (discontinued or sliding restraint plates), filling plates (discontinued or sliding filling plates), and restraining gaps with different sizes. The test results showed that the damage of the proposed joint was visually observed only on the replaceable core plates and was not observed at any other structural components. The SRP can effectively constrain the buckling deformation of the core plate in comparison to the discontinued restraint plates; thus, the proposed joint showed more stable force-deformation hysteresis. The continuity of the filling plates and the restraining gap size had little influence on the overall hysteretic response of the joint. However, a larger restraining gap caused larger stress in the restraint plates. Finally, numerical models of the test joints were established in ABAQUS and validated by the test results, which can serve as a reference for further research.