Spatiotemporal Vulnerability Analysis of Large-Scale Infrastructure Systems under Cascading Failures: Case of Water Distribution Networks

Large-scale water distribution networks (WDNs) are vulnerable to internal faults and external attacks. When exposed to various types of natural or artificial disasters, a glitch may trigger cascading failures and even paralyze the entire WDN. An improved load-based cascading failure model is proposed to analyze both structural and functional properties in a unified framework. The load-capacity relationship, load redistribution principle, and nodal breakdown probability are key factors needed to determine the evolvement of cascading failures. Different attack strategies that represent the scenarios of random failures, intermediate-level attacks, and catastrophic disasters are performed separately. The single-node attacks are repeated on each node to locate stricken components and identify weak points. Several novel metrics, such as node vulnerability, service level, and damage size, are adopted to characterize the spatiotemporal vulnerability of WDN. The simulation results illustrate that the traditional degree-based method inevitably results in the underestimation of potential losses in disaster scenarios. The improved load-based model that stresses network topology and physical significance can better reflect the reality. spatiotemporal vulnerability analysis is proven to be a powerful tool for optimizing system design and balancing the time-cost-reliability triad.