Simulation of pedestrian push-force in evacuation with congestion

The simulation of pedestrian push-force in evacuation with arched congestion before exit is presented based on cell automata. The generation, absorption, transfer and gather of pedestrian push-force are analyzed. Initial push-force facing to exit is generated based on the distance between pedestrian and exit. The scalar and vector sum of push-force are introduced to respectively describe the push effect and resultant force of outside jam push-force in crowded evacuation. Absorption coefficient and anti-crush coefficient are introduced to respectively describe the ability for pedestrian to absorb and resist the outside jam push-force. Simulation results show that the increase of absorption coefficient or anti-crush coefficient can effectively prevent pedestrian from being injured. It is found that three phases: weak protection, strong protection and complete protection are distinguished based on two critical absorption coefficients and an anti-crush coefficient. Pedestrian casualties will increase with the number of evacuation pedestrian rising. It is also shown that pedestrian casualties in jam occur in a reverse bell-shape symmetry zone before exit.