The Structural Risk Assessment of Existing Bridges in Tuscany (Italy) a Quick Survey-Based Method

The bridges and viaducts represent often the most crucial assets when assessing the resilience of a transportation network. They are, indeed, far less numerous and redundant if compared to the roads of the network. The recent collapses of bridges and viaducts all over the world testify the inadequate attention given to these structures and the need of developing methodologies suitable, on one hand, to be applied to a high number of structures in reasonable time and, on the other hand, to supply reliable indications to the network managers about the actions that need to be undertaken on each structure. These actions can consist in the simple ordinary maintenance or the execution of further investigations, structural checks, and relevant repairs. On the base of these considerations, the Authors present and discuss a visual inspection-based methodology for the structural risk estimation of existing bridges. The paper individuates and describes also the main parameters influencing the structural risk on the base of the inspections carried out on numerous existing bridges located in the Tuscany region (Italy). The information that had been collected during the visual inspections, subsequently allowed the analysis of the main characteristics and state of preservation of these structures.