Experimental and numerical investigations of beam-to-column joints with a double-core buckling-restrained connector

Based on the ideas of damage control and element replaceability, this paper proposes an earthquake-resilient, beam-to-column joint with a double-core buckling-restrained connector (DBRC). First, the composition and function of the joint are introduced, and the bearing capacities corresponding to four failure modes are theoretically calculated. Then, quasistatic tests were carried out on three specimens to investigate the influence of the stiffeners on the end plate and the ear plate connection on the hysteretic responses of the joints. The test results showed that the use of a DBRC can change the failure mode of the joint, in which the plastic deformation was concentrated in the DBRC, which dissipated most of the energy. The ear plate connection affects the bearing capacity of the joint, while the stiffeners have little effect on the hysteretic response of the joint. The finite element models for the joints were built using ABAQUS and validated by test results. Finally, parametric analyses were performed to determine the influences of the friction force of the core plate, the existence of a buckling restraining system, the thickness of the end plate and the cross-sectional area of the core plate. The results showed that these parameters mainly affect the in-plane and out-of-plane deformation of the core plate, end plate damage and joint damage distribution.