A STUDY ON TRAVEL TIME PREDICTION METHOD ON INTER-CITY EXPRESSWAYS USING TRAFFIC CAPACITY AT THE BOTTLENECK

Travel time information is one type of information system provided on inter-city expressways in Japan. The current method of calculating the travel time is based on the average running speeds in recent 5-minute intervals measured by vehicle detectors. This method is based on real-time traffic situation, however, transmitted travel times are not predicted real travel times for the drivers. To ensure the accuracy of information, a new method of predicting travel time using traffic capacity at the bottleneck is discussed in this paper. The method estimates travel time for jammed flow by comparing the number of vehicles and the capacity at the bottleneck and distinguishes free flow and jammed flow by comparing travel times of both cases. It is then applied to the traffic data on Tomei Expressway and accuracy of the computed travel times is discussed. For the covering abstract see IRRD E102946.