Emergency evacuation from multi-exits rooms in the presence of obstacles

To facilitate emergency evacuation, it is essential and important to investigate how system dynamics govern collective behaviors of pedestrians in panic. Although it has already been pointed out that appropriate arrangement of obstacles in a single-exit room can substantially improve evacuation efficiency, whether this conclusion can be carried over to multi-exits scenario still remains puzzling. Motivated by this, we propose an improved social force model to study the influence of the total number of pedestrians, their desired velocity and the specific locations of obstacles on evacuation efficiency for multi-exits configurations. Simulation results show that evacuation efficiency sensitively depends on the arrangement of obstacles. Specifically, there exists an optimal location for the obstacle where the total evacuation time is minimized, but not all the locations have a favorable impact on evacuation. This conclusion also holds for the dependence of evacuation efficiency on obstacles length. More importantly, the effect of obstacles, irrespective of being positive or negative, can be enhanced by increasing the number of pedestrians or the desired velocity. This work may shed some light on the drawing up of emergency scheme for multi-exits public-gathering places like stadiums and shopping malls.