Seismic Performance of the Buckling-Restrained Brace Central Buckle for Long-Span Suspension Bridges

In this paper, a novel central buckle composed of buckling-restrained braces (BRBs) is developed for long-span suspension bridges, and its preliminary design procedure is presented. Seismic performance of suspension bridges equipped with BRB central buckles is investigated and compared with those with conventional central buckles (e.g. rigid or flexible central buckles). Furthermore, the effect of BRB yield force, as well as the effectiveness of BRB central buckles combined with viscous dampers, is evaluated using parametric analyses. The results indicate that the BRB central buckle is more effective than other central buckles in reducing both the longitudinal girder displacements and force demands on towers during an earthquake. Furthermore, the combination of BRB central buckles and viscous dampers is a superior option for mitigating the seismic response of long-span suspension bridges.