ESTIMATION OF 18-KIP EQUIVALENT ON PRIMARY AND INTERSTATE ROAD SYSTEMS IN VIRGINIA

FOR FLEXIBLE PAVEMENT DESIGN PURPOSES, THE VIRGINIA DEPARTMENT OF HIGHWAYS USES THE AASHO METHOD OF DETERMINING THE 18-KIP EQUIVALENT SINGLEAXLE LOAD,. THE EVALUATION OF THE EAL-18 IS BASED ON ON-LOCATION TRUCK AXLE WEIGHT STUDIES . THESE STUDIES ARE EXPENSIVE AND TIME-CONSUMING AND HENCE ARE NOT USED FOR PAVEMENT REEVALUATION AND REHABILITATION. FOR THIS REASON, A METHOD BY WHICH THE EAL-18 COULD BE ECONOMICALLY AND QUICKLY ESTIMATED FROM THE ROUTINELY AVAILABLE RECORDS SEEMED DESIRABLE. THESE RECORDS ARE THE YEARLY TRAFFIC COUNT ON EACH SECTION OF THE PRIMARY, INTERSTATE, AND ARTERIAL SYSTEMS AND THE YEARLY RECORD OF THE WEIGHTS OF VEHICLES USING THESE SYSTEMS. IN THIS INVESTIGATION, SEVERAL METHODS WERE TRIED TO DETERMINE THE BEST ONE FOR ESTIMATING THE EAL-18 FROM ROUTINE AVAILABLE RECORDS. A METHOD INVOLVING THREE EQUATIONS WAS CONSIDERED THE BEST FOR THE FOLLOWING REASONS: IT PROVIDES A VERY GOOD CORRELATION WITH THE AASHO METHOD, DATA FOR ESTIMATING THE EAL-18 ARE READILY AVAILABLE FROM THE YEARLY REPORTS PUBLISHED BY THE VIRGINIA DEPARTMENT OF HIGHWAYS (AND THOSE OF MOST OTHER STATES), AND THE METHOD ACCOUNTS FOR THE WEIGHT AND COUNT OF TWO-AXLE, SIX-TIRE SINGLE UNITS, THREE-AXLE SINGLE UNITS, AND TANDEM TRAILER TRUCKS SEPARATELY, THUS PROVIDING GREATER ACCURACY IN THE EVALUATION. IT IS SHOWN THAT, EVEN IF THE ESTIMATED EAL-18 DEVIATES GREATLY FROM THE AASHO VALUE, THE EFFECT ON THE ULTIMATE PAVEMENT DESIGN IS VERY LITTLE. THE APPROACH COULD BE USED TO DEVELOP TRAFFIC PROJECTIONS IN CASES WHERE LOAD METER STUDIES ARE NOT FEASIBLE, FOR EXAMPLE, ON ROADS WITH HEAVY TRAFFIC WHERE VEHICLES CAN BE COUNTED BUT NOT WEIGHED.

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    • Publication of this paper sponsored by Committee on Flexible Pavement Design. 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:
    • Vaswani, N K
    • Thacker, D E
  • Conference:
  • Publication Date: 1973

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: pp 82-95
  • Monograph Title: Pavement systems analyses
  • Serial:

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Filing Info

  • Accession Number: 00206131
  • Record Type: Publication
  • ISBN: 0309022509
  • Files: TRIS, TRB
  • Created Date: May 15 1974 12:00AM