Abstract

Although there are studies that compared between indirect left-turn treatments such Median U-turn (MUT) or RCUT to the Conventional Intersection (CI) designs, very few have compared between the operational performances of MUT versus RCUT. Furthermore, few studies on the Quadrant Roadway Intersection (QRI) were found in the literature. The main objective of this paper is to assess different designs for the accommodation of left turns through indirect maneuvers. Traffic performance of the proposed intersection designs was evaluated based on micro simulation. The results revealed that the difference between the two designs, RCUT and MUT lies in the amount of traffic rerouted to the crossover intersections. Increasing the traffic downstream of the main intersection to the crossover intersection still has an effect on the main intersection#x2019;s operations. Proper design and spacing is needed at the crossover intersection to mitigate this effect. The analysis also showed that at higher volume levels, RCUT throughput becomes restricted compared to the MUT which was attributed to the left turn effect at the main intersection. However, the RCUT showed 52% improvement over the MUT in average speeds. RCUT also showed 66% over MUT in delay savings and one year cost reductions when compared to the conventional intersection at 200% volume level.