How to prioritize bridge maintenance using a functional priority index

The progressive aging of civil infrastructures makes it essential to develop managerial tools and instrument for planning maintenance activities. As public entities, typically in charge of the management of infrastructures, have limited resources, it is crucial to define clear prioritization criteria. Addressing this need, this work introduces the usage of a functional priority index for ranking infrastructures on the basis of the impact of their closure. The impact is expressed in terms of induced travel delay for people due to path detour. To estimate this delay an analytical strategy is introduced and applied to assess the priority index on a sample of 290 bridges in Lombardy. Relevant information are gathered integrating two data sources providing information on the transportation network and on the travel demand, i.e. road network data and Origin Destination matrices. The results of this application show that the method enables the identification of the most critical infrastructures and the detection, for each bridge closure, of the most impacted areas of the region and the most impacted hours of the day.