THE RELATIONSHIP OF ACCIDENTS TO LENGTH OF SPEED-CHANGE LANES AND WEAVING AREAS ON INTERSTATE HIGHWAYS

THIS ANALYSIS WAS CONDUCTED ON DATA COLLECTED FOR THE INTERSTATE SYSTEM ACCIDENT RESEARCH, STUDY II. THIS STUDY, WHICH WAS INITIATED IN 1961, HAS AS ITS OBJECTIVE THE DETERMINATION OF THE RELATIONSHIP BETWEEN THE GEOMETRICS OF THE INTERSTATE HIGHWAY SYSTEM AND ITS ACCIDENT EXPERIENCE. THE ANALYSIS REPORTED HERE IS CONCERNED WITH THE RELATIONSHIP BETWEEN LENGTH OF WEAVING AREAS, ACCELERATION LANES, AND DECELERATION LANES AND THE ACCIDENT EXPERIENCE OF THESE TYPES OF UNITS. ALSO CONSIDERED IN THE ANALYSIS WAS THE NUMBER OF VEHICLES UTILIZING THESE UNITS AND THEIR RELATIONSHIP TO THE TOTAL NUMBER OF VEHICLES USING THE INTERSTATE. RESULTS OF THIS ANALYSIS INDICATE THAT INCREASING THE LENGTH OF WEAVING AREAS WILL REDUCE THE ACCIDENT RATE AND THAT INCREASING THE LENGTH OF ACCELERATION LANES WILL REDUCE ACCIDENT RATES IF THE PERCENTAGE OF MERGING VEHICLES IS GREATER THAN 6 PERCENT OF THE MAINLINE VOLUME. INCREASED LENGTH OF DECELERATION LANES WILL ALSO REDUCE ACCIDENT RATES BUT TO A LESSER DEGREE THAN THE COMPARABLE INCREASE OF LENGTH OF ACCELERATION LANES. A SMALLER DECREASE IN ACCIDENT RATE BECOMES APPARENT AFTER THE DIVERGING TRAFFIC EXCEEDS 6 PERCENT OF THE MAINLINE TRAFFIC. ONLY THOSE VARIABLES SPECIFIED IN THE REPORT WERE CONSIDERED, AND THEREFORE APPLICATION OF THE RESULTS MUST BE LIMITED ONLY TO THOSE VARIABLES. /AUTHOR/

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  • Supplemental Notes:
    • Paper sponsored by Committee on Operational Effects of Geometrics and presented at the 49th Annual Meeting. 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:
    • Cirillo, Julie Anna
  • Discussers:
    • Bellis, W R
    • Byington, S R
    • Deacon, John A
  • Publication Date: 1970

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 17-32
  • Monograph Title: Relationships of highway geometry to traffic accidents
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00221079
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Oct 26 1970 12:00AM