A Graph Topology Method to Identify a Set of Cut Links in Critical Link Analysis for Transportation Planning

Transportation network criticality analysis aims to identify a set of links, known as cut links, based on their contribution to overall network connectivity. In recent decades, this topic has attracted increasing attention, and various graph-based methods have been proposed to assess link criticality. In this paper, we introduce a graph topology–based metric to identify a set of cut links whose removal would disconnect the network; we illustrate its application through a case study focused on improving link capacity in the planning process on a regional network. Previous methods typically use a full-scan approach, removing links one by one to calculate performance measures, or a max-flow min-cut method identifying a set of cut links in an s-t cut (from the single source s to the single sink t). The former approaches are time-consuming and fail to account for scenarios in which the degradation of multiple links simultaneously affects network connectivity; the latter does not support multiple origin–destination pairs. Our method addresses those limitations. Without loss of generality, our method can also be applied to identify cut links in link criticality analyses for vulnerability and resilience studies.