Abstract：Buckling-restrained braces (BRBs) are a new type of high-performance hysteretic dampers. BRBs are generally connected to frame structures by gusset plates which are welded to beam and column. However, the axial force of BRB is only considered into the current design approach of gusset plate while the effect of seismic frame action is generally ignored, leading premature fracture of gusset connection. In this study, the interaction between BRB corner gusset connection and steel frame is discussed by finite element method, and the effect of both BRB axial force and frame action is considered. Five FEM models were constructed by ABAQUS and the parameters of the models included the size of gusset plate, the connection type between gusset plate and frame, and free edge stiffener. A new type of gusset plate with sliding end plate and bolted connections to frame structure was proposed and comparison was made between the traditional and new gusset connections. The analysis results showed that compared with the gusset plate with larger size, smaller gusset plate dimension had smaller effect on the stiffness of frame structures which could reduce the seismic shear carried by the beams and columns. Also, smaller gusset plate exhibited better structural performance. The performance of gusset plate could not be significantly improved by providing free edge stiffeners onto the gusset plate. However, the negative effect of frame action and gusset plate on the stiffness of frame structures could be significantly reduced by adopting the proposed new gusset plate with sliding end plate, showing a promising gusset connection in steel buckling-restrained braced frame structures.
