A GIS-supported methodology for the functional classification of road networks

The management and monitoring of road networks require constant effort from road owners and managers. This study proposes a decision support method to assist decision-makers in planning interventions on road networks. The proposed method supports the functional classification of road networks and their hierarchy using well-defined rules and criteria. GIS tools are used to visualize the resulting classification. The analysis, which does not focus on single roads but on routes composed of one or more roads, proposes a hierarchization based on a set of indicators. These latter describe accessibility, functionality, geometrical and safety characteristics based on which routes can be classified according to different levels of importance. The indicators used are attributable to three main groups. The first group relates to infrastructure connectivity and accessibility; the second to functionality and performance (design speed, homogeneity of traffic flows, etc.) and the third describes the type of road according to variables related to width, tortuosity, accidents, etc. The proposed methodology can support the effective management of road networks and provide road practitioners with useful knowledge elements, also for monitoring road safety.