Multilevel Approach for Management of Existing Bridges: Critical Analysis and Application of the Italian Guidelines with the New Operating Instructions

This paper provides a discussion and thoughtful application on a large sample of the procedures for the classification of existing bridges recently adopted in Italy and defined within the Italian Guidelines for the classification, risk management, safety evaluation and monitoring of existing bridges and the early published Operating Instructions. Focusing on the classification at the territorial level, first the logic flows to the classification on the base of the structural risk are shown, resulting in the definition of the "structural warning class", providing the motivations that support the criteria for the definition of such procedures. Then, a statistical analysis of the results obtained from the classification of 661 existing Italian bridges is performed, focusing on the vulnerability classification and on the influence of each parameter on its evaluation.