Effectiveness of Traffic Sign Setting in Adjacent Tunnel Exit

When pre and post structural opening in adjacent tunnel groups are in close proximity, the effective setting of traffic sign in the tunnel exit may affect drivers’ vision and driving safety. This paper investigates the effectiveness of traffic sign setting in the adjacent tunnel exit. According to the adjacent tunnel groups’ characteristics and the conditions of how drivers make effective use of information from traffic signs, we propose an effective model in setting traffic sign based on the ergonomics and traffic theory using the driver's visual inert as well as the rate of change of the pupil area and traffic safety. The proposed model is tested in adjacent tunnel groups of Liuan-Wuhan expressway, and road safety, location, reasonable depression angle and exit distance of adjacent tunnel group traffic signs are calculated and analyzed. The rationality of this model has been verified. The results can provide guidance to set up exit traffic signs of the adjacent tunnel group scientifically.