Simulation of Crowd Evacuation in Subway Stations Under Flood Disasters

In recent years, floods have caused significant casualties and property damage worldwide. To investigate the evacuation dynamics of pedestrian in subway stations under flood invasion conditions, an evacuation model for pedestrian under flood situations is established by incorporating a cellular automata model and a hydrodynamic model. The effects of water depth, flow speed and flow direction on pedestrian movement and behavioral characteristics in subway stations are quantified. Crowd evacuation with the flood spreading process under various scenarios is simulated, and the egress time and pedestrian distribution are analyzed. It is found that the existence of flood reduces the evacuation speed and delays the evacuation process. With the increase of water depth and intake flow, it becomes more challenging for passengers to evacuate successfully. Under this circumstance, adding the number of safety exits and widening the exit width can significantly reduce the evacuation time. Besides, the pre-evacuation behavior hinders the movement process, and the rapid evacuation becomes more difficult due to the flood spreading during this period. The evacuation efficiency can be improved if the pre-evacuation time reduces. The study is useful to design evacuation plans and improve the emergency management level of subway stations under sudden flood disasters.