Gap Acceptance at U-turn Median Openings – A Case Study in Hanoi, VietNam.

抄録

U-turn median openings are locations where traffic congestion and traffic crashes are likely to occur. Understanding gap acceptance and driver behavior at these locations are crucial to reduce traffic congestion and traffic crashes. This paper tried to consider the geometry (i.e., median width and opening distance) in the analyses of gap acceptance. In addition, an inverse Time-to-Collision was introduced to analyze the gap acceptance from a safety viewpoint. Our result indicated that when the U-turning vehicles perceive a possible collision, they are likely to reject the gap. We concluded that the narrower median width and longer opening distance significantly result in a higher probability of gap acceptance. Based on these findings, our paper proposed some suggestions to road designers and managers at the U-turn locations, which can minimize the likelihood of traffic crashes at this facility.