INVESTIGATION OF LANE DROPS

THE OBJECTIVES WERE TO EVALUATE THE EFFECTIVENESS OF SAFETY AND TRAFFIC OPERATIONS OF LANE-DROP CONFIGURATIONS ON SEVERAL FREEWAYS. AERIAL PHOTOGRAPHS WERE TAKEN OF TRAFFIC VOLUMES AT 3 LANE-DROP SITES IN THE LOS ANGELES AREA, TIME- HISTORY TRAJECTORIES OF ALL VEHICLES WERE COMPUTED, AND MEASURES OF TRAFFIC OPERATIONS (SPEEDS AND CONCENTRATIONS) AND SAFETY (POTENTIAL COLLISIONS) WERE DETERMINED. NO SIGNIFICANT DIFFERENCES IN SAFETY EFFECTIVENESS AMONG THE 3 CONFIGURATIONS WERE IDENTIFIED, BUT 1 SITE AT WHICH THE PAVEMENT MARKINGS CAUSED THE 2 HEAVILY TRAVELED LEFT LANES TO MERGE HAD SIGNIFICANTLY LOWER SPEEDS AND HIGHER CONCENTRATIONS THAN EITHER OF THE OTHER SITES. THE AERIAL PHOTOGRAPHIC DATA REDUCTION SYSTEM DEVELOPED DURING THE STUDY ALLOWS OBJECTIVE ANALYSIS OF THE COMPLEX INTERACTION OF TRAFFIC AT LANE DROPS OR AT OTHER FREEWAY CONFIGURATIONS. HOWEVER, THE SYSTEM NEEDS FURTHER DEVELOPMENT BEFORE IT CAN BE AN ECONOMICAL TOOL FOR THE TRAFFIC ENGINEER. /AUTHOR/

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  • Supplemental Notes:
    • 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.
  • Authors:
    • Goodwin, Browne C
    • Lawrence, Robert L
  • Publication Date: 1972

Media Info

  • Media Type: Digital/other
  • Features: Figures; References;
  • Pagination: pp 45-61
  • Monograph Title: Freeway operations and control
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00226399
  • Record Type: Publication
  • Report/Paper Numbers: No 390 PP 36-9
  • Files: TRIS, TRB
  • Created Date: Sep 19 1972 12:00AM