Planning and Presenting the Optimal Model for the Network Emergency Evacuation after an Earthquake

Earthquake is a common natural disaster that often brings about wide-ranging catastrophic consequences. The post-crisis assessment of conditions generally indicates poor performance in evacuation routing and planning, leading to incoordination and waste of time and network capacity. Therefore, this study presented a heuristic, integrated solution to determine evacuation routes in the shortest time possible using an algorithm based on network analysis and the definition of safe nodes and arcs based on crisis conditions. The proposed flow optimization model employs MCNFP to find the shortest evacuation routes from each node to the safe zone and guide the maximum possible flow through this route. The model's efficiency was tested using 12 small networks with different combinations of nodes and vehicles and 10 medium networks with different numbers of nodes and similar demands. Then, the running times of each MCNFP algorithm and the proposed model (P-M) were compared. The results showed that the evacuation time increased by increasing the number of nodes and the routing complexity. In addition, increasing the number of vehicles in small networks increased the evacuation time. Finally, the research results confirmed the higher speed of the heuristic algorithm than MCNFP in network evacuation.