EXPERIMENTAL AND NUMERICAL INVESTIGATION ON SEISMIC PERFORMANCE OF RING-BEAM CONNECTION TO GANGUE CONCRETE FILLED STEEL TUBULAR COLUMNS

Abstract

This paper presents an investigation on seismic performance of a ring-beam connection that is used to connect reinforced gangue concrete (RGC) beam to coal-gangue concrete-filled steel tubular (GCFST) column. Two specimens, including an interior connection with two beams and an exterior connection with one beam, were designed and fabricated for experimental tests under full-reversing cyclic loads at beam ends. In addition, finite element models which corresponded to tested specimens were developed using ABAQUS to conduct numerical simulations of the composite connection subjected to the combined axial and cyclic loads. The feasibility of the developed model to predict failure modes and load-deformation response of the connection was validated by comparing with test results. The response of the ring-beam connection to cyclic loads was examined with respects to the load-bearing capacity, deformation resistance, stiffness and strength degradation, ability to dissipate energy in a seismic event, and ductility. With numerical models, parametric analysis was completed to evaluate the influences of material and structural parameters on connection resistance against cyclic loads. Based on the results of parametric studies, a restoring force model of skeleton curve for the ring-beam connection was developed in terms of ultimate capacity and corresponding deformation. The results provided practical suggestions for the application of ring-beam connection to GCFST column in the projects.