Extreme natural events and bridge collapses: statistical insights in Italy

This study investigates bridge collapses and severe damage events in Italy over the last three decades, focusing on the role of natural hazards under changing climatic conditions. A database of 180 cases was compiled from publicly available sources, including newspapers, technical bulletins, and scientific literature. Each event was classified by bridge typology, material, damage severity, and most probable triggering cause. Results show that 73 % of failures were linked to natural hazards, with floods and landslides representing the dominant triggers, while anthropogenic factors accounted for 27 %. In particular, floods emerged as the predominant cause of collapse, generally leading to global or partial failures that nevertheless undermines the overall functionality of the structure. Statistical analyses indicate a significant correlation between failures and extreme precipitation, which has increased in frequency in recent years as a consequence of climate change. In the 2018–2024 period, the association is particularly pronounced: more than 70 % of collapses attributed to natural hazards occurred in conjunction with documented extreme rainfall events. These findings suggest that Italy's aging bridges may be increasingly vulnerable to climate-driven hazards and highlight how comprehensive multi-hazard risk assessments, targeted monitoring, and the integration of climate-resilient principles into bridge management and design practices can contribute to enhancing long-term structural safety.