Influence of Roadside Infrastructure on Driving Behavior

Abstract

This paper describes the results of a driving simulator study that focused on the influence of roadside infrastructure on drivers’ speed choice and the lateral placement of their vehicles. A review of the Roadside Infrastructure for Safer European Roads detailed accident database revealed that lateral positioning and speed of the vehicle were two of the primary factors leading to crashes. The driving simulator study served as a means to include human factor principles into roadside infrastructure guidelines. Roadside features studied included trees, guardrails, barriers, panels, and emergency lanes. It was found that drivers tended to move away laterally from safety barriers when they first approached them and that they slightly slowed down. The type and size of a safety barrier appeared to be less important; only its presence had an effect. Trees were not found to affect the speed of the driver unless they were close (2 m) to the road edge on a rural road with an 80-km/h speed limit, and this effect faded rather quickly. There was no influence on speed if the trees were more than 4.5 m from the lane edge. The fact that trees along the road are not considered to be a hazard, with drivers not adjusting their behavior, makes trees even more dangerous.