This paper introduces a prefabricated concrete-filled double-skin steel tubular (CFDST) joint designed for easy repair following a disaster. To investigate the influence of endplate thickness
axial compression ratio
bolt diameter
concrete filling degree and shape of inner steel tube on the seismic performance of the joints
quasi-static tests were performed on six scaled 1∶2 joint specimens. The bearing capacity
ductility
stiffness degradation
strength degradation
and energy dissipation capacity of the joints were analyzed. The failure modes of joints included endplate bending
flanges buckling
weld cracking between endplate and flange
bolt warpage
and bolt fracture. The load-displacement hysteretic curves were plump
indicating the joint has good energy dissipation capacity. The displacement ductility coefficients of joints were greater than 4.89
indicating that the joint has good plastic deformation ability and ductility. The strength degradation coefficients were basically maintained at 0.9-1.0
showing good bearing capacity stability. Increasing the endplate thickness significantly improved the seismic performance of the joint. Increasing the axial compression ratio
the concrete filling degree
and replacing the inner circular steel tube with a square steel tube increased the bearing capacity of the joint
and changing the bolt diameter had little effect on the bearing capacity. Changing the axial compression ratio and the bolt diameter had little effect on the energy dissipation of the joint. Increasing the concrete filling degree and replacing the inner circular steel tube with a square steel tube noticeably decreased the energy dissipation of the joint. The failure modes and bearing capacity of the joint obtained by the established nonlinear finite element model were in good agreement with the test results.