Engineers often adopt spiral tunnels to change the routes to a certain elevation of mountainous area in western china. The driving conditions of spiral tunnels are different from general area. And the chief problem is to solve the value of the circular curve radius. Road traffic system is a complex coupling system of human, vehicle, road and environment, in which the driver factor is the critical factor. Therefore, from the angle of driver's behavior, this paper studies the changing rule of driving behavior with the radius of spiral tunnel circular curve, and determines the range of radius. Based on UC-win/Road, a three-dimensional simulation model of spiral tunnel is constructed, then design the simulation experiments, Arrange the ten drivers to collect driving behavior data with different radius under four working conditions: left-turn downhill, left-turn uphill, right-turn downhill and right-turn uphill. The experimental results show when the radius is greater than 930m, the coefficient of variation of the driving speed increases obviously. With the increase of the radius of the circular curve, the lateral displacement of the vehicle decreases gradually. Finally, based on the concept of "self-explanatory road", this paper determines the radius range of the spiral tunnel. Considering the safe distance between parallel vehicles and the lateral displacement, gives the minimum radius.

CICTP