Evacuation experiments in vertical exit passages in an underwater road shield tunnel

Evacuation experiments were conducted to examine the movement speed and evacuation capacity in an underwater shield road tunnel where vertical evacuation passages were installed. Behavioral results were collected through several field experiments aimed at investigating vehicle evacuations, the time required to open vertical evacuation passages, slide and stairs descending with and without counter flows. The results show that the individual movement speed in staircase was lower than the speed in slide, but the average Occupant Flow Rate (OFR) in staircase was higher than the OFR in slide. The probable reasons were discussed and analyzed. Females had worse performance when opening the exit door than males. The upstairs movement of firefighters was observed not negatively affect the evacuation performance of occupants down stairs. The replicated experiments showed that appropriate training or drills can help improve the movement speed of occupants. The results of this study will be essential to evaluate evacuation capacity and occupant behavior on stairs and slides of underwater shield tunnels.