|
Title: SOME OBSERVATIONS OF HIGHWAY TRAFFIC IN LONG QUEUES
Accession Number: 00778950
Record Type: Component
Record URL: Availability: Transportation Research Board Business Office 500 Fifth Street, NW Find a library where document is available Abstract: The arrival times of vehicles traveling southbound along a two-lane, bidirectional highway were recorded at eight neighboring locations upstream of a bottleneck caused by an oversaturated traffic signal. Cumulative curves constructed from these observations describe completely and in great detail the evolution of the resulting long queues. These queues formed directly upstream of the signal when the signal's service rate fell below the southbound arrival rates, and never formed away from the bottleneck. The predictability of bottlenecks like the one studied here can be exploited to manage traffic more effectively. The behavior of vehicles within the queue, however, was rather interesting. Although the flow oscillations generated by the traffic signal were damped out within 0.8 km (0.5 mi) of the bottleneck, it was found that other oscillations arose within the queue farther upstream, at varied locations, and then grew in amplitude as they propagated in the upstream direction. Thus, the queue appeared to be stable close to the bottleneck and unstable far away. Oscillations never propagated beyond the upstream end of the queue, however; that is, the unusual phenomena always arose after the onset of queueing and remained confined within the queue. Some of these findings run contrary to current theories of traffic flow. Because the data set collected in this study is unprecedented in scope and detail and so that it may be of use to other researchers, it has been posted on the Internet and is fully described here.
Supplemental Notes: This paper appears in Transportation Research Record No. 1678, Highway Capacity, Quality of Service, and Traffic Flow and Characteristics.
Language: English
Corporate Authors: Transportation Research Board 500 Fifth Street, NW Authors: Smilowitz, K RDaganzo, C FCassidy, M JBertini, Robert LPagination: p. 225-233
Publication Date: 1999
Serial: ISBN: 0309071046
Features: Figures
(6)
; References
(13)
; Tables
(4)
TRT Terms: Subject Areas: Highways; Operations and Traffic Management; I71: Traffic Theory
Files: TRIS, TRB, ATRI
Created Date: Nov 29 1999 12:00AM
More Articles from this Serial Issue:
|