Investigation of Gap Acceptance at Roundabouts in Qatar

Abstract

Modern roundabouts are a popular method to control traffic at intersections. In this type of roundabouts, priority is given to the circulating flow, and the approaching vehicles have to find a gap to merge with the flow under a yield condition. These types of maneuvers are impacted by many factors including the human behavior, the vehicle type, and the number of approaching lanes. In this work, one of the major factors that affect the capacity of roundabouts is investigated; that is the critical gap value. This work aims to evaluate the value of the critical gap at some of the most popular types of roundabouts in Qatar. The critical gap value was identified at a number of roundabouts with different configurations in Doha. The outcome of this work can benefit the engineering society and public agencies in Qatar and the region to plan and design similar facilities.