A bi‐level emergency evacuation traffic optimization model for urban evacuation problem

Abstract This paper introduces a pioneering bi‐level emergency evacuation traffic optimization model (BEETOM), crafted to expedite the evacuation process within urban road networks. The innovative upper‐level model offers simultaneous optimization of evacuation departure times and routes, while the lower‐level model focuses on refining traffic signal timing to mitigate delays and queue formation across intersections. To enhance the model's computational efficiency, a distributed solving algorithm is introduced, marking a significant stride in optimization technology. Implemented in two evacuation case studies, the BEETOM model showcases its profound impact by reducing total evacuation time by 6% to 20%. More impressively, it achieves a substantial decrease in both the average travel time and delays experienced by evacuees during evacuation, ranging from 7% to an astonishing 60%. This remarkable efficacy underscores the model's capability to devise highly effective evacuation strategies, particularly valuable for managing large‐scale emergencies or terrorist incidents in urban settings. The BEETOM model stands as a significant contribution to urban emergency management, offering a strategic tool to significantly enhance evacuation efficiency and safety.