Multi-risk assessment of bridges and viaducts according to classes and logical operators: conceptual analysis and statistical paths

The assessment of road bridges and viaducts is critical for effectively managing existing infrastructures. Recent efforts have increasingly focused on multi-risk methodologies to systematically identify and quantify various potential risks and then properly monitor structural health over time. Following several notable failures—including the highly publicized 2018 partial collapse of the Polcevera viaduct, aka the “Morandi’s Bridge”—the Italian Higher Council of Public Works introduced detailed innovative guidelines and operational procedures to govern risk arrangement and administration, safety valuation, and monitoring these structures. This paper contributes to the topic in two main ways: first, it provides a conceptual exploration and investigation of the whole process that connects the considered parameters to risk classifications, aiming to clarify the full range of parameters, their roles, and their potential groupings. Second, it delivers an in-depth statistical analysis of risk classifications, representing the “a priori” risk probabilities as outlined by the procedure. This analysis on distribution patterns also includes targeted studies referred to some typical cases of bridges and viaducts.