2015 Volume 11 Pages 1919-1930
As a speed-reduction measure on a motorway, Central Nippon Expressway Co., Ltd. has been conducting field research of light-emitting devices placed at regular intervals on the shoulder of a road, and controlling the light emission in arbitrary light-emission patterns to control vehicle running speeds. In this paper, operational experiments conducted on the Tomei Expressway to alleviate the traffic congestion caused by sags and tunnel bottlenecks are introduced, and the effects of the installed system on the flow rate and vehicle movement for both the no-congestion and the congested situations are discussed. An analysis is carried out using vehicle detector data and video tape recorder (VTR) image analysis. The results show that the speed of vehicles is affected by the devices, and a significant increase in throughput is observed for the congested situation, whereas there is only a small effect on the flow rate for the no-congestion situation.
