VOLUME WARRANTS FOR LEFT-TURN STORAGE LANES AT UNSIGNALIZED GRADE INTERSECTIONS

THE DERIVATION IS DESCRIBED OF VOLUME WARRANTS AND DESIGN CHARTS FOR LEFT-TURN STORAGE LANES AT UNSIGNALIZED GRADE INTERSECTIONS ON FOUR-LANE AND TWO-LANE HIGHWAYS. THE DESIGN CHARTS ARE BASED ON A THEORETICAL ANALYSIS AND ON A SERIES OF FIELD STUDIES OF TRAFFIC BEHAVIOR AT INTERSECTIONS. THE ANALYSIS IS BASED ON A QUEUEING MODEL IN WHICH ARRIVAL AND SERVICE TIMES ARE ASSUMED TO FOLLOW A NEGATIVE EXPONENTIAL DISTRIBUTION. THE ARRIVAL RATES ARE DETERMINED BY THE VOLUMES OF LEFT-TURNING, THROUGH OR ADVANCING AND OPPOSING TRAFFIC, AND BY THE TIME INTERVAL REQUIRED BY THE VEHICLE TO CLEAR THE ADVANCING LANE. SERVICE RATES ARE DETERMINED BY VOLUME OF OPPOSING TRAFFIC, AND BY THE TIME INTERVAL REQUIRED TO MAKE A LEFT TURN MANEUVER. A LEFT-TURN STORAGE LANE IS WARRANTED BY TRAFFIC VOLUMES WHEN THE RATIO OF ARRIVAL RATE TO SERVICE RATE EXCEEDS A SPECIFIED VALUE, WHICH VARIES WITH TYPE OF HIGHWAY AND VEHICLE SPEED. THE REQUIRED STORAGE LENGTH OF THE LANE MAY ALSO BE DETERMINED. FIELD STUDIES WERE CONDUCTED OF TRAFFIC BEHAVIOR AT SEVEN UNSIGNALIZED ONTARIO INTERSECTIONS. QUESTIONNAIRES ON SUITABILITY OR CHART RECOMMENDATIONS FILLED OUT BY HIGHWAY DEPARTMENT REGIONAL TRAFFIC ENGINEERS AT 80 ONTARIO INTERSECTIONS INDICATED GENERAL AGREEMENT.

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  • Supplemental Notes:
    • Paper sponsored by Committee on Traffic Control Devices. 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
  • Authors:
    • Harmelink, M D
  • Publication Date: 1967

Media Info

  • Media Type: Print
  • Features: Appendices; Figures; References; Tables;
  • Pagination: pp 1-18
  • Monograph Title: Aspects of traffic control devices
  • Serial:

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Filing Info

  • Accession Number: 00225087
  • Record Type: Publication
  • Source Agency: CANADIAN GOOD ROADS ASSOCIATION
  • Files: TRIS, TRB
  • Created Date: Aug 11 1994 12:00AM