A realistic and comprehensive risk and resilience assessment of THE networks must integrate estimates of damage to the surrounding physical environment and downtime of other critical networks that affect the overall performance of THE networks. The disrupted built environment is usually modeled as a collection of individual structures for which the probability of reaching different damage states is calculated independently, and results subsequently used to estimate the number and severity of casualties, loss of homes, and incidence of other consequential hazards like debris generation and fire follow-ing the earthquake. Lifelines and utilities beyond the ones considered in detail in this research (WP2, WP3), must be treated also as a collection of individual components that will each experience loss of functionality when faced to a seismic event. Results from these analyses then become inputs for the detailed analyses of THE networks in WP2. In a real natural disaster scenario, the first earthquake impact on the integrated system is hence characterized by the limited access to essential services and supplies that are critical for emergency recovery.

To test the interaction and interdependency of THE networks with the built environment, WP4 will deploy the models developed in WP2 within a real geographical setting populated by other physical infrastructure and people that interact with them. Concretely, we propose to develop an exposure model of two interconnected major urban areas; the metropolitan Santiago and the neighboring coastal cities of Valparaíso-Viña del Mar. Work in WP4 will involve the study of the interaction between physics-based models of WP2 and the environment, and the methodology will serve as a testbed for the formulation of an integral framework for evaluating seismic risk and resilience in the Chilean context. Results from this integrated analysis will allow identification of the critical components and interdependencies in THE networks and propose mitigation measures to lower the risk and improve resilience. The scale of this application roughly covers half of the national population, and hence can be used as a pilot for application to other territories.