Impact of Narrower Lane Width

This driving simulator study investigated differences in the influence of lane width reduction on speed profiles and lateral positions in real-world and simulator conditions. The use of driving simulators has been expanding in transportation research. This use raises the question of the simulators’ validity. The study was developed in two steps. In the first step, an experiment was conducted with the INRETS (French National Institute for Transport and Safety Research) driving simulator. Forty-three drivers drove in the simulator. Two configurations of lane widths (3.5 m and 3 m) were tested, both chosen in reference to a previous French field study carried out on a rural road to assess the impact of lane width reduction and the provision of a hard shoulder on driver behaviors (speed, lateral positioning). In the second step, results were compared with the results of the French field study. The comparison showed that, as in the field study, reducing the lane width had no impact on speeds but did induce the participants to drive closer to the center of the road. It also showed that oncoming vehicles induced subjects to move toward the right side of their lanes. Finally, the results showed a relative behavioral validity.