INFLUENCE OF LATERAL DISPLACEMENT CURVE ON THE SEISMIC PERFORMANCE OF MULTI-STORY SELF-CENTERING FRICTION ENERGY DISSIPATION BRACED STEEL FRAMES BASED ON DISPLACEMENT DESIGN

The lateral displacement curve needs to be defined in advance when employing the direct displacement-based seismic design method, and the influence of the curve on the design results and the seismic performance of the structure require further study. Taking the self-centering friction energy dissipation braced steel frames as examples, and considering the structural nonlinearity and the number of stories, the influence of three typical lateral displacement curves on the seismic performance of the structures was analyzed. Results showed that the lateral displacement curve had little effect on the design base shear force of the 3-story braced frame, but had a noticeable effect on the base shear force of the 6-story structure. The design values of inter-story drift ratio varied with the lateral displacement curve, resulting in a great change in story design stiffness. The actual lateral displacement curve was linear-type and bending-type for 3-story braced frame and the 6-story structure, respectively. It is recommended that the linear-type displacement curve could be used for the low-story structure below 3-story and the bending-type displacement curve for the multi-story structure about 6-story. This study is expected to provide a reference for the selection of lateral displacement curves of this type of braced steel frame structures.