Effect of S-shaped guardrails on pedestrian crowd flows in bottleneck areas

The influence of obstacle effects on personnel traffic flow is a hot topic in the evacuation field. However, research is lacking on the use of S-shaped guardrails in daily life. Based on previous studies, we placed two S-shaped guardrails in front of an exit. Thereafter, a real person evacuation experiment was designed, and 97 volunteers were recruited to the application of this structure in terms of crowd management and evacuation. The evacuation time, visual trajectory, spatial and instantaneous velocity, regional density, and other data were studied in detail. The study found that in the 97-person experiment, the addition of the S-shaped guardrails prolonged the evacuation time. Considering speed and density, the average instantaneous velocity of pedestrians in the structure was higher and maximum area density smaller. In addition, a phenomenon was observed in the study that large angle turns eradicated the zipper effect generated by a narrow channel width, preventing the accumulation of high density and pressure. This, is expected to provide some reference for channel design in real life.