Advances in the Seismic Design of Special Truss Moment Frames

摘要

The inefficiency of ordinary truss moment frames to resist large lateral deformations imposed by seismic loads led to the development of special truss moment frames and their adoption in the AISC Seismic Provisions for Structural Steel Buildings. In an effort to expand on the scope of those provisions, which currently specify two types of arrangements for the special segment, this paper explores an innovative approach of using fuses to engage the ductile truss frame action. The lateral response of these systems was evaluated using non-linear pushover analyses. The fuse types included details that utilize plate moment hinging or friction damper slipping within the diagonal members of the special segment. The incorporation of friction damping devices in particular was found to provide ductile response with well-defined performance levels. Upon identifying individual member contributions to the overall lateral resistance, a rational approach to the design of special truss moment frames utilizing friction dampers is presented.