Bridge vulnerability and hazard assessment for risk-based infrastructure management

A research agreement between Regione Lombardia and Politecnico di Milano has been recently established to define criteria and guidelines for maintenance and management of the regional roadway infrastructure. A synthetic risk-based methodology has been formulated for bridge prioritization on a documentary basis, taking into account the main risk factors and functional losses or traffic interruption of the road network due to maintenance or unavailability of individual bridges. The methodology has been implemented and applied considering a sample of about 400 bridges. Bridge prioritization is established based on a two-level structure-network risk assessment combining bridge technical priorities, informed by structural-hydraulic vulnerability and hazard, and infrastructure functional priorities, associated with road network exposure. This paper presents the risk assessment framework established at the bridge level in terms of vulnerability and hazard factors.