Seismic performances of bridges are essentially determined by the behavior of the structural elements capable to transfer horizontal actions like piers, bearings and structural connections or restraints. Aging structures are unavoidably subject to degradation of the performances of such elements and, therefore, the investigation of the possible consequences of structural deterioration on the seismic performances of existing bridges is a basic issue with significant scientific interest and technological impact.

A comprehensive study of this topic requires to progress in three main directions: a) development of nonlinear modeling and analysis tools for the capacity of deteriorated structural elements, b) extensive investigation of the correlation between deterioration of structural elements and seismic performances of bridges, c) evaluation of the effectiveness of currently available intervention techniques.

In this work, an overview of some first, preliminary, results of a research project currently ongoing on this topic are presented. In particular, the influence of corrosion of steel bars on the overall seismic performances of a bridge with Reinforced Concrete piers, is discussed on the basis of a sample case study.