An evacuation model considering pedestrian crowding and stampede under terrorist attacks

As a global problem, terrorist attacks result in significant casualties and property damage every year. However, previous studies have focused on the direct casualties inflicted by terrorists, while neglecting the indirect injuries stemming from crowding and trampling among pedestrians. To investigate the impact of the dual mechanism of terrorist attack and stampede on pedestrian evacuation, a pedestrian evacuation model based on the cellular automata model is proposed. First, the movement of pedestrians is influenced by panic, and they may be killed or injured with a certain probability due to terrorist attacks during movement. Next, the role of forces in the social force model is introduced to determine whether pedestrians will fall due to crowding, and the fallen pedestrians may recover after cushioning or be trampled and attacked to death. Finally, the evacuation process under terrorist attacks is reproduced by simulation, and the effects of factors such as panic control coefficient, attack intensity, fall coefficient, terrorist location and number, and exit distribution and width on evacuation are discussed. Our research can provide some reference and basis for the design of building structures and emergency management during terrorist attacks.