00099660

Component

http://onlinepubs.trb.org...s/trr/1975/533/533-002.pdf

https://scholar.google.co...rter&publication_year=1975

Previous research has indicated that limiting traffic demand in an underwater vehicular tunnel can produce substantial increases in flow rates and speeds. A pretimed control system consisting of a standard traffic signal was used to meter traffic entering the Baltimore Harbor Tunnel. Four different cycle lengths and splits were tested, and the results were compared to those obtained from the uncontrolled situation. The increase in flow rates and speeds of 3 of the control strategies over those in normal operation showed that even a simple control system is capable of significantly benefiting traffic flow through a tunnel. An evaluation methodology was applied to the control alternatives; both quality of flow and flow rates were considered. Primary emphasis was placed on a methodology requiring a maximum of time and effort in data collection. The operations of the tunnel was observed in its 2 basic states--congested and uncongested. The quality of flow in a tunnel is poorest on the downgrade, better on the level section, and best on the upgrade. The results of this research should help to make pretimed, tunnel-bottleneck control a more practical engineering tool.

Publication of this paper sponsored by Committee on Freeway Operations. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.

01411394

pp 22-33

1975

Transportation Research Record

54th Annual Meeting of the Transportation Research Board

030902384X

Print

Figures (6) ; References (10) ; Tables (2)

Bottlenecks; Control systems; Evaluation; Traffic congestion; Traffic flow; Traffic signal cycle; Traffic signal timing; Traffic speed; Vehicular tunnels

Highways; Operations and Traffic Management

TRIS, TRB

Nov 5 1975 12:00AM

• CORQ-A MODEL FOR PREDICTING FLOWS AND QUEUES IN A ROAD CORRIDOR
• DESIGN TECHNIQUE FOR PRIORITY-ACCESS RAMP METERING
• DETECTING FREEWAY INCIDENTS UNDER LOW-VOLUME CONDITIONS
• DEVELOPING FREEWAY PRIORITY-ENTRY-CONTROL STRATEGIES
• DEVELOPMENT AND EVALUATION OF INCIDENT-DETECTION ALGORITHMS FOR ELECTRONIC-DETECTOR SYSTEMS ON FREEWAYS
• EVALUATION OF A PROTOTYPE WARNING SYSTEM FOR URBAN FREEWAYS
• MATHEMATICAL EVALUATION OF TRAFFIC CONTROL ALTERNATIVES FOR RESTRICTED FACILITIES
• OPERATIONAL ANALYSES OF FREEWAY MOVING-MERGE SYSTEMS
• SIMPLIFIED APPROACH TO MODELING FREEWAY OPERATIONS AND CONTROL