Quantifying temporal vulnerability of urban multi-modal transit networks under interdependent cascading failures

Multi-modal public transit networks (MPTNs) are vulnerable to service disruptions that might diminish their utility and cause severe consequences. The present study assesses the vulnerability of MPTNs under different operating scenarios. By combining network topology, dynamic evolution, and passenger interchange characteristics, we propose a vulnerability assessment framework. The proposed assessment relies on dynamic flow redistribution rules based on the interlayer transfer coefficient and sequential network characteristic indicators, which are crucial for improving service quality and mitigating cascading failures. The results indicate that MPTNs are less vulnerable as station capacity increases. Moreover, MPTNs are more robust during off-peak scenarios. However, when a failure occurs, the vulnerability of the network increases with the interlayer flow coefficient. These insights facilitate the determination of reasonable capacity parameters for stations within specific ranges. Furthermore, the study enables the identification of critical cascade-propagation steps for effectively managing and mitigating cascading failures following a disruption.