A Graph Theory Approach to Resilience of Transportation Infrastructure Systems: Accounting for Traffic Volume with Weighted Links

A new paradigm for complex systems performance and maintenance decision-making is developing in the form of resilience engineering. Depending on the subject area, different definitions of resilience exist. In this project, we adopt a definition appropriate for resilience in transportation systems: the ability of the system to recover and adapt to external shocks, which include natural, intentional and technogenic disasters and failure due to poor design. These disturbances can ultimately affect the smooth and efficient operation of systems and may demand a shift of process, strategies and/or coordination.
This project builds off existing research and uses graph theory methods to develop a methodology to determine the resilience index of any transportation infrastructure system. This project also introduces weighting into the methodology based on traffic volume. Two weighting strategies are offered. It is shown that the inclusion of either weighting strategy increases the resilience of infrastructure systems and provides a more complete model. Finally, the methodology developed is applied to the network of major state and federal highways in Albemarle County, Virginia, to illustrate the process of determining a transportation infrastructure system’s resilience index.