RELATIONSHIP BETWEEN CURVATURE AND ACCIDENT EXPERIENCE ON LOOP AND OUTER CONNECTION RAMPS
THE RELATIONSHIP IS EXAMINED BETWEEN ACCIDENT RATE AND CURVATURE ON LOOP AND OUTER CONNECTION RAMPS OF THE INTERSTATE HIGHWAY SYSTEM. RAMP CHARACTERISTICS CONSIDERED INCLUDE MAXIMUM CURVATURE, LOCATION OF RAMP, ENTER OR EXIT DIRECTION WITH RESPECT TO THE MAIN-LINE UNIT, AND AVERAGE DAILY TRAFFIC. ACCIDENTS PER MILLION VEHICLES ARE USED AS THE PRIMARY INDICATION OF ACCIDENT EXPERIENCE. RESULTS OF THE INVESTIGATION INDICATE THAT ACCIDENT RATES INCREASE WITH MAXIMUM CURVATURE FOR ALL RIGHT ENTERING OR EXITING LOOPS AND OUTER CONNECTIONS EXCEPT RURAL LOOPS. ACCIDENT RATES ARE LOWER ON RIGHT ENTERING OR EXITING OUTER CONNECTIONS WITH NO CURVATURE (LESS THAN 1 DEG) THAN ON THOSE WITH CURVATURE FOR ALL BUT ONE URBAN ADT CATEGORY. ALL URBAN RIGHT ENTERING OR EXITING LOOPS AND OUTER CONNECTIONS, EXCEPT URBAN LOOPS, SHOW A POSITIVE CORRELATION BETWEEN ADT AND ACCIDENT RATE. THE EFFECT OF TRAFFIC VOLUME ON RURAL RAMP SAFETY FOR VARIOUS CURVATURE EXHIBITED MIXED RELATIONSHIPS. /AUTHOR/
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Supplemental Notes:
- Paper sponsored by Committee on Operational Effects of Geometrics. 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
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Authors:
- Yates, John G
- Publication Date: 1970
Media Info
- Media Type: Print
- Features: Figures; References; Tables;
- Pagination: pp 64-75
- Monograph Title: Relationships of highway geometry to traffic accidents
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Serial:
- Highway Research Record
- Issue Number: 312
- Publisher: Highway Research Board
Subject/Index Terms
- TRT Terms: Average daily traffic; Crash rates; Curvature; Interchange ramps; Traffic volume; Urban areas
- Identifier Terms: Interstate Highway System
- Old TRIS Terms: Freeway entrances and exits; Freeway ramps
- Subject Areas: Highways; Safety and Human Factors;
Filing Info
- Accession Number: 00221082
- Record Type: Publication
- Files: TRIS, TRB
- Created Date: Oct 26 1970 12:00AM