The research on driver’s visual adaptability is of great significance to the operation safety of urban underwater tunnels. The real vehicle test was carry out to collect natural driving data. Based on the study of the drivers’ pupil area distribution, the mathematical model of pupil area variation when entering the tunnel under time series was constructed, and a method of visual adaptability evaluation was established. The results demonstrated that (a) The pupil area of the driver increased continuously when entering the tunnel, until the average pupil area was 3.318 times of that before entering the tunnel when adapting to the black hole effect. (b) When entering the tunnel in the daytime, the driver’s visual adaptability outside the tunnel was better than that inside the tunnel. (c) The side walls on both sides of the ramp in front of the entrance and the shading shed at the entrance can enhance the driver’s visual adaptability to the black hole effect. The research results can provide theoretical support for the safety management of urban underwater tunnel entrance section.

CICTP