Experimental Study on Pedestrian Behavior and Traffic Capacity of Cross Passage in Highway Tunnel

In order to provide a foundation for cross passage design and fire risk evaluation in highway tunnel, an experimental platform of pedestrian evacuation from cross passages in highway tunnel was built and a software based on video image was developed to analyze pedestrian trajectories in the evacuation process. Pedestrians' evacuation behaviors and walking speeds in normal and emergency situations were studied with different cross passage widths (1.4-2.0 m), and the evacuation capacity of cross passages with different widths and illuminations was obtained based on the walking speed of pedestrians. The results show that in the order of entering the cross passage, pedestrians' walking speeds slow down, and the magnitude of speed reduction also gradually reduce. Compared with the earliest individuals to enter the cross passage, the latest individuals will reduce their walking speeds by 40%-50% in average. In addition, the width of the cross passage determines the layer numbers of pedestrians across the passage. With the passage width increasing, pedestrians' walking speed and passage traffic capacity both increase; specifically, every 0.1 m increase in the width of cross passage can bring an increase of 12.3-13.5 persons per minute in the traffic capacity. Under low illumination conditions, the traffic capacity of cross passage is about 15% lower than that in good illumination conditions, and pedestrians thus should pay more attention to enhance their self-protection.