Seismic Reliability Analysis of Deteriorating Representative U.S. West Coast Bridge Transportation Networks

For optimal functioning of societies and economies, understanding how networks of lifeline infrastructure, e.g., bridge networks, perform after a hazard is essential. Such hazard resilience can be quantified by considering the reliability of the network against disconnection or blocked network flow; however, a major challenge associated with such analysis is making sure that the component models are realistic while keeping the analysis accurate. For this reason, a methodology has been developed for realistic bridge network modeling using the following components: representative bridge classes identified by clustering a database, cutting-edge time-variant fragility models of bridges, and a multiscale network reliability analysis method, which accounts for the impact of bridge structural deterioration on network-level performance. Using the proposed methodology, the broader effects of various deterioration scenarios are investigated as well as the impacts of spatial correlation and the use of subjunctive representations of nodes in the network. The network-level relative importance of each network route is further investigated using conditional probability importance measures. Furthermore, the integrity index will be used to explore the network's reliability and optimal strategies to improve hazard resilience.