Group Dynamics in Pedestrian Crowds

Recent crowd disasters highlight the importance of properly planning and designing large urban events and public spaces to enhance the safety of people in a crowd during evacuations. Pedestrian crowd dynamics are empirically investigated with an interdisciplinary approach (i.e., social sciences, computer science, and traffic engineering) focusing on the effect of groups and their proxemic behavior and interactions while walking. Empirical evidence achieved from urban in-field observations and laboratory experiments are presented and compared. Results indicate that the proxemic behavior of walking groups has a negative effect on walking speed when flow is irregular (primarily because of the need for members to maintain spatial cohesion during locomotion). These results have important implications for the design of common metrics to characterize spatial interactions among pedestrians and for the validation of models to replicate crowd dynamics that consider the effects of groups under normal and emergency conditions