Bridges, Tunnels and other Transportation Structures
This study puts forward a state-of-the-art framework to quantify and evaluate post-earthquake resilience of the highway networks. Resilience, in this context, denotes the required time for recovering the functionality of the highway network. During an earthquake, bridges in the network may experience different levels of damage, and because of the experienced damage, those bridges may be fully or partly closed for traffic. In this study, it is investigated how such closure for repairing or reconstructing bridges may affect the entire functionality of the highway network. The proposed framework takes into account the interdependencies among the bridges in the highway network by considering the impacts of a damaged bridge on the repair or construction time of other bridges in the network. In this regard, agent-based models are developed to simulate the bridge performance following earthquakes. The framework takes into account the uncertainty in the bridge performance, seismicity rate of the considered area, as well as the uncertainty in the repair and construction time of different bridge types. Such a developed framework can be used to better understand the impacts of the seismic hazards on communities and to inform decision-making in terms of post-earthquake response and planning for future events to improve the post-earthquake resilience and functionality of the highway network in that area. The proposed framework is then applied to a specific case study, which is a highway bridge network located in the State of Texas. The main motivation of studying this case stems from the increased rate in the seismicity of this particular region of Central and Eastern United States, which is largely believed to be as a result of human activities such as petroleum activates or wastewater disposal. Such induced earthquakes generally occur in areas that historically have had negligible seismicity, and the infrastructure in these states was likely designed for no to low seismic demands, making them vulnerable to seismic damage. Therefore, the framework is applied to the highway network of that area to see how potentially induced seismic hazards may affect the resilience of highway network. To do so, ground motion prediction equations representing seismic hazard of this region, and fragility curves representing seismic vulnerability of bridge infrastructure in that area are utilized. The results reveal both immediate impacts of potentially induced seismic hazards on bridge infrastructure as well as the effects of such hazards on the functionality of the highway network during the restoration phase considering the interdependencies among the bridges in the highway network.