Finite Element Analysis of Seismic Performance of Outer-Ring Cover Plate Joints Between Concrete-Filled Square Steel Tubular Column with Built-in I-Shaped CFRP and Steel Beam

Considering the difficulty of construction and low assembly degree of ring plate outer joint, a new type of ring plate beam column outer joint was proposed. The force transfer mechanism, yield mechanism, failure mode, stiffness and energy dissipation capacity of typical specimens were numerically simulated by using the finite element analysis software ABAQUS. Based on the above research, the effects of cover plate size, aspect ratio of tube and CFRP configuration rate on the seismic performance of the joint were deeply analyzed. The results showed that the yield of the joint began in the middle of the flange of the steel beam in the plastic hinge area, extended to the web through the flange, and then yielded in the whole section. The ultimate rotation angle of the joint was 0.053 rad, and its rotation performance was good, which showed semi-rigid connection. The bearing capacity of the joint could be enhanced by adding the measurement of the cover plate and the aspect ratio of tube. The most suitable size should be: the width of the cover plate should be 0.7~0.9 times the height of the steel beam; the thickness of cover plate should be 0.7~1.2 times the thickness of steel beam flange; the ratio of aspect ratio of tube should be 30~50; the CFRP configuration rate could satisfy the bearing capacity and deformation capacity of the column itself.