Seismic Performance Analysis of Buckling-Restrained Braced Steel Frames with Ductile Castings

Buckling-restrained brace (BRB) steel frames with ductile castings are proposed to solve the fracture failure of welded joints between buckling-restrained braces and frames after rare earthquakes. In this paper, quasi-static tests are conducted on two one-story, one-bay steel frames to study their mechanical behaviors, including stress distribution, failure mode, energy dissipation, and skeleton curve, and finite element models are established for verification. Subsequently, 22 models with different parameters of the BRB steel frames with ductile castings are analyzed using ABAQUS. Results indicate that the new frame system has good energy dissipation; it can confine the inelastic deformation of the structure to the ductile castings and BRB. It also satisfies the 1/50 maximum elastic-plastic drift angle set by the Code for Seismic Design of Buildings. The BRB with ductile castings connected to the frames by bolts can relieve the stress distribution in the beam-column region, which can be assembled and replaced after the earthquake.