Earthquakes can significantly disrupt societal functioning, cause ecological damage, and lead to loss of human lives and property, warranting a coordinated and efficient response to mitigate their negative impacts. Preparedness against earthquakes entails a pre-disaster planning aspect and a post disaster operational aspect. In the JTRP study “Emergency Earthquake Routes for the State of Indiana; Part I: Criteria for Selection of Primary Routes: Transportation Aspects”, a multicommodity maximal covering network design formulation based optimization methodology was proposed to identify a critical routes sub-network for the Indiana component of the Wabash Valley Seismic Zone in the INDOT Vincennes District. Addressed from a planning perspective, the primary objective was to strengthen the bridges on this sub-network through an effective seismic retrofit scheme so as to increase the likelihood of the critical routes being available to first responders following an earthquake to maximize response effectiveness. The critical routes of a transportation network are the set of routes whose functionality is critical to the effectiveness of earthquake response, or equivalently, the routes that provide the quickest response (least travel time) to most of the population (maximal coverage). The above study considered all Interstates, US Roads and State Roads in identifying the critical routes sub-network that should be seismically strengthened. However, Part II of that study “Route Seismic Vulnerability Aspects”, which addressed the bridge seismic retrofit aspects, considered only the sub-network corresponding to the National Highway System and the National Truck Network in identifying the bridges for retrofit. Hence, the first objective of the current study is to analyze whether the sub-network corresponding to the National Highway System and the National Truck Network compares well, from a costs-benefits perspective, to that suggested by the previous study. The second objective, which arises in the operational context, aims to determine a methodological framework for dynamically rerouting first responders when part of a route is unavailable after an earthquake. It provides back-up operational response plans when specific road segments of the recommended critical routes sub-network fail during an actual earthquake.

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Earthquake Response, Critical Routes Network, Dynamic Re-routing, SPR-3060

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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