查看文章

Transportation networks are important in providing accessibility and promoting the safe and efficient movement of people and goods. Yet they are so fragile and vulnerability to disruptions. Analyzing and understanding vulnerability to disruptions in transportation networks is hence an important topic. In this paper, we develop network-based accessibility measures using a combined travel demand model for assessing vulnerability of degradable transportation networks. The combined travel demand model is formulated as a variational inequality problem to model different travel behavioral responses of network users when the network is disrupted. Utility-based accessibility measures derived from the combined travel demand model are used to assess network vulnerability at different spatial levels. The results indicate that the accessibility measures proposed in this paper are capable of measuring the consequences of both demand and supply changes in the network and have the flexibility to reflect the effects of different travel choice dimensions on the network vulnerability.