An Original Model of Infrastructure System Resilience Jingjing Kong Slobodan P. Simonovic June 2, 2016

Contents Introduction Infrastructure Network Formalization Infrastructure System Resilience Simulation Framework  

886 disasters in Canada from 1950

Infrastructure system response Cascading failures throughout the whole infrastructure system at regional and national scales. Effective protection and recovery strategies are hard to make. Infrastructure system resilience is often overestimated. Most researches use system robustness or system recovery rapidity of individual infrastructure system as resilience quantification metrics. Figure. Interdependence of different infrastructure (Rinaldi et al., 2001)

Infrastructure System Model Network of networks /multilayer network Nodes of the infrastructure networks have three coordinates Edges Intra-network links Inter-networks links Information network Power grid , Water supply network Street network

Basic Infrastructure Dependence Patterns Node – Node dependence ( ) State of node is dependent on the state of node Node – Edge dependence ( ) State of node is dependent on the state of edge Node/Edge – Path dependence ( / ) State of node or edge is dependent on State of path Node/Edge – cluster dependence ( / ) State of cluster is dependent on State of node or edge Geographic Dependence ( ) State of all infrastructure elements located at the same location A are affected by a disturbance simultaneously

Infrastructure Interdependence Formalization Interdependence of two individual networks Four dependence: First order impacts Combination of first order impacts Interdependence of three or more individual networks Diverse combinations of two individual networks dependences Higher-order impacts: Chain and cycle reactions

Infrastructure System Dynamics Mechanism Figure. Adaptive capacity of an infrastructure after a disturbance Buffer time Malfunction time Repair time Figure. Dynamic process of an infrastructure after a disturbance

Definition of infrastructure system resilience Based on the definition by Bruneau et al (2003) , Simonovic et al (2013), Presidential Policy Directive 21 and other sources focusing on engineering resilience of networked infrastructures. Infrastructure system resilience is the systems’ ability to resist (prevent and withstand) possible hazards, absorb the initial damage from hazard, and recover to normal operation levels. Reactive absorptive capacity AND Proactive restorative capacity Robustness, Redundancy, Resourcefulness, Rapidity

Infrastructure system performance Resourcefulness: the capacity to identify problems, establish priorities, and mobilize resources when conditions exist that threaten to disrupt some elements, or a system. Robustness: the ability of a systems to withstand a given level of stress without suffering degradation or loss of function. Rapidity : the capacity to meet priorities and achieve goals in a timely manner in order to contain losses and avoid future disruption. Typical Performance Process of Infrastructure System

Infrastructure system resilience Typical Performance Process of Infrastructure System

Simulation Framework Multilayer Infrastructure Network Model Infrastructure System Dynamic Mechanism interdependence TB, TR, TM Restorative Strategy Single Layer Infrastructure System Performance Disaster Scenario (removal of network elements ) Multilayer Infrastructure System Resilience

Thank you! Jingjing Kong kjingjin@uwo.ca RESILIENT INFRASTRUCTURE June 1–4, 2016 Thank you! Jingjing Kong kjingjin@uwo.ca