Pedestrian merging behavior analysis: An experimental study

Merging flows involve complex interactions between pedestrians, which will restrict the efficiency of the evacuation process in emergency situations, such as fires. However, experimental research on merging behavior is limited. This paper describes pedestrian behavior in a merging channel where the branch flow joins the main flow at a junction area. The width of the main channel was fixed at 3.2 m while the branch had a changeable value of 0.8 m, 1.6 m and 2.4 m, respectively. Up to 295 university students took part in the experiments and all trajectories were extracted using the mean-shift algorithm. Lane formation was found downstream in the main channel and the increasing amplitude of the lane width formed by the branch flow became weaker with the increasing width of the branch channel. The saturated flow was approximately 4.9ped/s (1.5ped/m/s) and when the branch channel was 2.4 m, the main and branch channel became mutual bottlenecks to each other. Moreover, microscopic characteristics of pedestrian interaction were analyzed. Velocity-position relationships with the 1.6 m and 2.4 m branch widths showed the velocity in the main channel decreased when pedestrians got close to the merging area and the velocity in the branch channel was suppressed significantly compared to that with the 0.8 m branch. Density in the corner increased when the branch width increased and reached about 6ped/m² when the branch width was 2.4 m. What's more, pedestrian flow in the branch became jammed in this situation. The results can be used to calibrate pedestrian simulation models and improve public infrastructure design.