'Vehicle Detectors (double-sensor type)' are implemented frequently on major Expressways in Japan; the main purpose of implementation of detectors has been just counting the vehicles passed. Recently, 'travel time information' become served utilising average speed calculated by the detectors. This paper deals with fast detection technique of the traffic congestion occurred at capacity bottleneck of basic freeway section (such as sag section) on Expressways, and reveals difference of traffic flow characteristics at the instance of congestion occurrence between at just-upstream section of the bottleneck and at far-upstream section of the bottleneck. The platoon characteristics of just before the occurrence of traffic congestion are also examined.
Samenvatting