Methodology for Evaluating and Improving Road Network Topology Vulnerability

The situation that the road network loses its connectivity due to links´ unavailability is discussed in this paper. Since the connectivity of the network is always determined by its topological structure, the problem is defined as topology vulnerability. Mincuts frequency vector is chosen as the index for evaluating the network´s topology vulnerability. The larger the index is, the more vulnerable the network is. Two ways for improving network´s topology vulnerability are analyzed. Based on the network´s topology vulnerability index, links´ criticality index is calculated. The larger the index is, the more critical the link is, as its failure is more likely to disconnect the network. Then the better the improvement effect of its disaster-resistant ability´s enhancement will have. Taken greedy triangulation network as reference, adding links onto the network will also improve its topology vulnerability. The topology vulnerability index is used for determining the priority of construction scenarios. A trial network is used to present the algorithm of the methodology proposed and Sioux Falls network is taken as an application example.