PSI - Issue 84

Alessandro Scala et al. / Procedia Structural Integrity 84 (2026) 497–504

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Within this framework, the present study investigates how extreme precipitation events affect the severity and typology of bridge failures triggered by natural hazards, using a national database of 180 bridge collapse and severe damage cases recorded in Italy over the last 30 years (Scala et al., 2025). The analysis focuses on failures attributed to floods and landslides and examines damage levels in relation to structural type and construction material, with the aim of providing an interpretation oriented toward infrastructure management.

Fig. 2. Biannual number of extreme weather events recorded in Italy (2011–2024) based on CittàClima data (https://cittaclima.it). The extreme events include floods, flash floods, landslides, windstorms, and other weather-related disasters. A polynomial trend-line is also plotted. 2. Database and data classification The analyses presented in this study are based on a national database collecting information on collapses and severe damage affecting bridges and viaducts in Italy over the last 30 years. The database includes 180 documented cases and was originally developed to investigate the relationship between extreme natural events and bridge failures at national scale (Scala et al., 2025). The information was retrieved from publicly available sources, including newspaper articles, technical reports, official communications issued by the Italian Civil Protection Department, and contributions from the scientific literature.

Fig. 3. Examples of bridge failures that are part of the database. (a) Bridge collapsed in Madonna del Monte (A6 motorway, Liguria, Italy): collapse caused by the interaction with a debris flow that caused the loss of a span. (b) Motta di Molinella bridge (Emilia Romagna, Italy): total collapse of the structure by river flooding during an extreme event. (c) Himera Bridge (Sicily, Italy): slow landslide interaction causing progressive deformation on a girder structure. (d) Ponte di Ca’ Stronchino (Emilia Romagna, Italy): collapse of two spans attributed to overtopping during a period of extreme events in Emilia Romagna in May 2023.