Applicability of Unconventional Intersection Designs Over Pretimed Signalized Intersection Design Along a Coordinated Corridor

Abstract

The focus of this research is on evaluating the performance of three unconventional intersection designs [Michigan U-turn (MUT), superstreet, and continuous green T-intersection (CGT)] over existing pretimed signalized intersection design along Highway 49 in the city of Charlotte, North Carolina, USA. MUT and superstreet intersection designs eliminate the left turns from side streets and replaces them with a combination of right-turn and U-turn movement. However, in the case of CGT, a separate continuous lane is provided for the through movement at one of the approaches of the intersection. Ten signalized intersections were identified along the selected study corridor. A base model was developed using Synchro/SimTraffic traffic simulation software and validated by comparing traffic volumes (provided as input vs. simulated) and through visual audits. Underperforming intersections were identified along the study corridor and were replaced with the aforementioned unconventional intersection designs. Performance measures, such as the total vehicle delay, the total delay per vehicle, and the total number of stops, were computed and compared with the existing condition. The results obtained indicate that the selected unconventional designs are not applicable at all considered intersections. The use of unconventional intersection designs could reduce the average delay per vehicle at the corridor level. However, the use of unconventional intersection designs could result in an increase in the total number of stops at the corridor level. The findings and recommendations from this research help practitioners assess the applicability of the selected unconventional intersection designs over the conventional pretimed signalized intersection design.