AbstractWhen drivers are approaching a signalized intersection at the onset of ayellow change interval, they must decide whether to stop or cross theintersection. This can be a difficult decision when the vehicle is locatedwithin the dilemma zone and the result is sometimes a rear-end crash due to asudden stop. Dilemma zone is defined as an area close to an intersection inwhich a vehicle can neither stop safely before the intersection nor clear theintersection without speeding before the red signal comes on. This research studiesthe driver behavior during the amber onset in the signalized intersection.One signalized intersection was selected in Damascus city to collect data forthis purpose. Data was collected using video recording technique. Data wereabstracted, processed and analyzed using programs developed for this purpose. Thestudy examined 226 drivers on the amber onset, 42.47% of them were found to beconflicted by the dilemma zone phenomenon. 51.25% of them conflicted withaccelerating, 42.5% who stopped abruptly, and 6.25% who passed during the redsignal.Key words: dilemma zone, amber onset, clearing distance, stopping distance
Traffic movement is considered a compound phenomenon that is impacted by behavioural, economic, and physical aspects. It is performed within the context of an urban system that consists of road networks and crossings, where the movement crouches to depend. The measuring of identifying their size and densities and current problems helps to Improve and development for roads and streets network existing and important is intersections for purposes the accessibility, potentiality of future intersections, and network development towards constructing a composition to raise the quality and the efficient performance of roads and streets. The study was dependent on a traffic survey for intersections, areas of urban intersections, and the road network of Al-Ramadi city, as well as the number of vehicles that generated a large volume of traffic flow. The use of the program (HCS 2010) to detect appropriate for purposes decreasing traffic congestion and delayed trip time in the areas based on existing and future districts that generate different types and purposes of journeys to lessen the delay trip time to lessen traffic congestion. Therefore, research looks at both sides: first, a study of the existing intersections of the main road network and urban streets, including an examination of the components and shapes of these intersections in the study area; second, an examination of the importance placed on these intersections by the planning and design process.