Simulation-Based Evacuation System for Large-Scale Urban Road Network Considering Traffic Conditions

Abstract

In case of an emergency, it is necessary to consider the impact of all traffic conditions on implementing the evacuation program accurately and reliably because there are still some private vehicles running in the evacuation area. To tackle this issue, this paper presents a large-scale simulation-based evacuation system from multiple evacuation depots to multiple safety depots considering traffic conditions, including three parts: traffic conditions acquisition, evacuation path planning, and microsimulation evaluation. Firstly, the traffic conditions related to link travel time between two points are estimated by considering private vehicles running on the road network and the rescue bus vehicles participating in the evacuation. A multi-path choice model for a dynamic time-varying network is then proposed, which might solve the evacuation paths with the minimum of evacuation time. Experimental results show that the proposed method could have higher accuracy than the traditional static path planning, as well as higher computational efficiency than the dynamic algorithm. Finally, the variable cell transmission model (VCTM) is improved to deduce the characteristics of evacuation traffic flow under the estimated traffic conditions, which can be used to recognize the bottlenecks in the road network and re-optimize traffic control measurements. The contrastive analysis results showed that the improved VCTM is in good agreement with the operation results of the popular microscopic simulation software VISSIM.