Microscopic dynamics of escaping groups through an exit and a corridor

Abstract

This research explores the dynamics of emergency evacuations in the presence of social groups. The investigation was carried out in the context of the Social Force Model (SFM). We included attractive feelings between individuals belonging to the same social group, as proposed in Ref. Frank and Dorso (2016). We focused on the escaping dynamics through an emergency exit and through a corridor. We confirmed the results appearing in Ref. Frank and Dorso (2016) for a desired velocity of 4m/s, but further extended the analysis on the emergency exit to the range 1–8m/s. We noticed that the presence of groups worsens the evacuation performance. However, very strong feelings can improve the escaping time with respect to moderate feelings. We call this phenomenon “Closer-Is-Faster”, in analogy to the “Faster-Is-Slower” effect. The presence of social groups also affects the dynamics within a corridor by introducing an additional slow-down in the moving crowd.