The subject of this study is the time delay at major bottlenecks on the road network. Actual delays were measured at several well-known bottlenecks on the motorway network in the Netherlands. Separately, the development of queues over time was studied for some twenty bottlenecks during a period of 15 years. Subsequently, the results are discussed with a focus on the following questions: Do queues stabilise over time; and is there an upper limit to the time delay? The study is unique with respect to the time-delay results. Driving times over road sections were obtained by a calibrated algorithm using the speed-flow measurements of the motorway control system that is installed on large parts of the main road network of the country. Queuing delay as a function of time was calculated per bottleneck for more than 50 successive working days. The results reveal a remarkably accurate view on the average delay as a function of time of day as well as on its day to day variation. (A)
Abstract