A methodological proposal for the analysis of bridges inspections data according to the Italian Guidelines

The question of maintenance and monitoring of bridges gained attention during the last decade, especially in Italy, after some serious collapses. The first emergency phase was the census and the visual evaluation of the state of maintenance and preservation of existing heritage to highlight the critical conditions for security. For this reason, in 2020 the Italian Ministry of Transport and Infrastructure enacts Guidelines, based on a multilevel approach, which allows to save time and resources by deepening the analysis only on the bridges in the worst state of conservation. After two years of inspections, a lot of data had been collected. The data concerns both the geometrical/typological characteristics and the defectiveness of bridges. In the present work, the authors discuss the data of a sample of inspected bridges belonging to some Regions of the Italian infrastructural system trying to analyse them from a statistical point of view. The objective is to standardize an analysis methodology and apply it to a larger number of samples to obtain useful and significant information to refine the inspection procedure and, eventually, to educate algorithms for the a priori provision of the defectiveness level, suggesting a possible prioritization of the bridges to be inspected.