Rural Intersection Enhancement and Driver Behavior Study

Project summary:

The dynamics of high speed on major roads and crossing vehicles from minor roads at rural thru-STOP intersections create ample opportunity for severe, often deadly, angled collisions (Preston et al., 2003). The J-turn intersection is a roadway design for divided highway, thru-STOP intersections which decreases the points of conflict at an intersection, by restricting straight crossing and left-turning movements from the minor road across the major highway to reduce some of the most serious crashes at these high-risk intersections. Past research at UMN has identified errors novice drivers make in navigating a J-Turn intersection upon their first exposure. Further, as any intersection (including J-Turns) poses risks due to the interaction between major and minor road traffic, a past study examining sight distances at undivided, rural thru-STOP intersections found that placing drivers stopped at the stop sign closer to the intersection reduced speeds of mainline drivers and made them more responsive to imminent collision scenarios. Such movements would also increase the sight distance of the crossing driver. The study will use a mixed-methods approach to experimentally manipulate J-turn intersections and undivided, thru-STOP intersection markings and signage in a driving simulation and validate J-turn driver behavior findings in a field observation of a newly constructed J-turn intersection. The goal of the work is to provide design guidance for markings and signage at thru-STOP intersections to support driver decision making and safe crossing behaviors.