Restoration of services in disrupted interdependent infrastructure systems

Abstract

Understanding the fragility induced by multiple interdependencies is one of the major challenges in the design of resilient infrastructures. These rippled failures greatly increase their vulnerability to disruptions along with delays in their restoration efforts. Networks feature a bidirectional dependence such that power stations depend on communication nodes for control, and communication nodes depend on power stations for their electricity supply. This research investigates the effects of disruptions on the interdependent infrastructures of electric power and telecommunications networks and performs an empirically based analysis to understand their interdependence and its effects in restoration efforts. The aftermath of extreme events such as hurricanes, earthquakes, and pandemic outbreaks provide a unique opportunity to obtain experimental evidence that the critical infrastructures are indeed interdependent. Empirical analysis including Granger causality tests are performed to assess interdependency between the networks following the event. After interdependency and its duration are properly assessed, a system dynamics model is proposed to provide insights on how to reduce restoration times by appropriate selection of model parameters.