Comparison of Seismic Upgrading Techniques Applied to an Existing Prestressed Concrete Bridge

Various solutions can be applied for seismic upgrading of bridges based on the improvement of strength or ductility. However, the use of advanced technologies as passive control systems by seismic isolation or dissipative devices can be more convenient because there is a definite reduction in the action transferred to foundations, which leads to the avoidance of expensive interventions. In this paper, a comparison between various retrofitting techniques is proposed considering the case study of a prestressed existing bridge that has a double cantilever configuration. The results confirm the efficiency of the passive control systems; furthermore, the maintenance of the base isolation system appears more onerous than that of the dissipative device system realized with an external contrast structure.