A multi-grid model for pedestrian evacuation in a room without visibility

The evacuation process from a room without visibility is investigated by both experiment and modeling. Some typical characteristics of blind evacuation, including the preference of choosing left-hand side direction and following behavior, are found from the experiment. Meanwhile, different strategies of conflict resolution are observed in the experiment. Based on the experimental observation, a multi-grid model for evacuation without visibility is built in this paper. Simulation results of the model agree well with the experiments. Furthermore, the effect of exit width, number of exits and initial density on evacuation are studied, and results show that exit width has little impact on evacuation time and increasing number of exits is an effective way to decrease evacuation time. Finally, simulations of evacuation under normal and no visibility are compared, and the differences for two conditions are predicted. The comparison results also demonstrate that the blind evacuation is much slower than evacuation under normal visibility, which is match with the practical experience. A similar point is that the distributions of time interval in both situations satisfy power-law relation approximately. The study may be useful for understanding the egress behaviors and developing efficient evacuation strategy and plan to guide pedestrian evacuation without visibility.