2025-03-19
2024-08-27
2024-01-04
Abstract— At-grade intersections are one of the most critical components of urban transportation networks. They are major impedance, which create a significant interruption to traffic flow. Traffic control is required to regulate the flow of at-grade intersections to achieve the greatest efficiency and reduce traffic delay for road network users. Several models and studies are performed to determine the control type while designing new at- grade intersections. This research focuses on comparing the performance of an intersection under two types of control, roundabouts and metered roundabouts. The experimental design evaluated a four-leg at-grade roundabout with several traffic congestion levels and different traffic distribution scenarios on the approaches. The research results show that metered roundabouts increase delay at high traffic volumes and does not improve the operation of roundabouts. In addition, the metered roundabouts may increase the delay at an intersection when the traffic on the approaches does not show a major approach or when there is a major approach with a significantly high left-turn percentage.