Pedestrian collective motion in competitive room evacuation

GARCIMARTÍN, A.; PASTOR, J. M.; MARTÍN-GÓMEZ, C.; PARISI, D.; ZURIGUEL, I.

Scientific Reports

Springer Naure

Año: 2017 vol. 7 p. 1 - 9

When a sizable number of people evacuate a room, if the door is not large enough, an accumulationof pedestrians in front of the exit may take place. This is the cause of emerging collective phenomena where the density is believed to be the key variable determining the pedestrian dynamics. Here, we show that when sustained contact among the individuals exists, density is not enough to describethe evacuation, and propose that at least another variable ?such as the kinetic stress? is required.We recorded evacuation drills with different degrees of competitiveness where the individuals are allowed to moderately push each other in their way out. We obtain the density, velocity and kinetic stress fields over time, showing that competitiveness strongly affects them and evidencing patterns which have been never observed in previous (low pressure) evacuation experiments. For the highest competitiveness scenario, we detect the development of sudden collective motions. These movements are related to a notable increase of the kinetic stress and a reduction of the velocity towards the door, but do not depend on the density.