A Study on the Lane Width of Car-Only Urban Underground Road

Theoretical analysis combined with experimental study was conducted to determine the proper lane width for urban car-only underground road. Vehicle trajectory data were collected in the experiment using three different ways including naturalistic driving experiment, video image processing and driving simulation. Lateral offset of each vehicle moving on the lane were obtained to determine the lane width. The results shows that for the car-only underground road, the design vehicle width is 1.8m,considering the safety margin and driving comfort, the minimum lane width 3m and 3.25m are reasonable and safe for the design speed 60km/h and 80km/h respectively.