Road Network Vulnerability Analysis: Case Study Considering Travel Demand and Accessibility Changes

Road network vulnerability analysis is helpful in the improvement of vulnerable links with proper maintenance investments and management strategies. This paper addresses issues that received limited attention in past studies: the estimation of travel demand after the link disruption, and the analysis of accessibility variation. An Activity-Based Model was used to estimate travel demand changes due to link closure, and link importance is evaluated with a set of vulnerability indicators; accessibility changes induced by link closure are presented and discussed. The vulnerability analysis has been conducted to the road network of the municipality of Dolo, northern Italy. Considering spatial distribution of activities and trips, results obtained with Activity-Based Model are more reliable than those obtained with Fixed Demand Model, which has unrealistic assumptions of unchanged travel demand after network degradation. These findings are relevant for appropriate resource allocation strategies, which depend on correct link vulnerability analysis and ranking.