A Comparison of Transportation Network Resilience under Simulated System Optimum and User Equilibrium Conditions

Resilience is a characteristic that indicates system performance under unusual conditions, recovery speed, and the amount of outside assistance required for restoration to its original functional state. Resilience is important for daily events, such as vehicle crashes, and more extreme events, such as hurricanes and terrorist attacks. Transportation resilience has ten dimensions: redundancy, diversity, efficiency, autonomous components, strength, collaboration, adaptability, mobility, safety, and the ability to recover quickly. This paper examines the influence of the system optimal and user equilibrium traffic assignments on the last four dimensions. No widely accepted measurement of resilience is available for transportation systems; this paper presents multiple metrics for the four examined contributing components that will aid future development of a single measure of resilience. An application of these measures to a test network found that user equilibrium results in better adaptability and safety while system optimum yields better mobility and faster recovery