Seismic Retrofit of a Three-Span RC Bridge with Buckling-Restrained Braces

This study evaluated the potential benefits of using buckling-restrained braces (BRBs) to seismically rehabilitate straight bridges. For this purpose, a three-span RC box girder bridge was used as a case study. A three-dimensional model was developed using software to incorporate BRBs between bent columns. The BRB inelastic behavior was represented using the Menegotto–Pinto model to reproduce its isotropic and kinematic strain-hardening properties. Nonlinear time-history analyses were performed to assess the seismic performance of the BRBs and the existing RC bridge. The structure was evaluated under several performance limit states using far-field records, which were scaled to the maximum considered earthquake level at the site using an average interval scaling method. The results show that BRB components improve the seismic performance of bridges under serviceability and ultimate limit states by decreasing drifts in the bents and by reducing the steel and concrete strains of the original RC columns. The retrofit BRBs redistribute and dissipate energy in the transverse direction of the bridge, and reduce the potential failure in the concrete columns and abutment shear keys.