APPLICATION OF AASHO ROAD TEST RESULTS TO DESIGN OF FLEXIBLE PAVEMENTS IN MINNESOTA: TRAFFIC ANALYSES

A TRAFFIC STUDY WAS CONDUCTED TO DETERMINE APPROXIMATIONS VALID TO ESTIMATE THE DISTRIBUTION OF AXLE WEIGHTS WITHIN A GIVEN TRUCK TYPE AND THE DISTRIBUTION OF THE VARIOUS TRUCK TYPES OVER A GIVEN SECTION OF ROADS. THE TOTAL VOLUME OF TRAFFIC TO USE THE ROADWAY AT EACH TEST SECTION WAS ALSO DETERMINED. THE DISTRIBUTION AND VOLUMES ARE USED TO: (1) CALCULATE THE TOTAL EQUIVALENT 18,000-LB AXLE LOADS WHICH THE SECTION HAS BEEN SUBJECTED TO SINCE IT WAS LAST RESURFACED, AND (2) DETERMINE WHAT TRAFFIC PARAMETERS BEST PREDICT THE TOTAL EQUIVALENT LOADS ON A PAVEMENT SECTION AND HOW ACCURATELY THESE PARAMETERS PREDICT THE EQUIVALENT AXLE LOADS. THE TRAFFIC STUDY INCLUDED THE FOLLOWING OPERATIONS ON 41 OF THE 50 TEST SECTIONS: (1) WEIGH ALL TRUCKS PASSING A LOCATION DURING A 16-HOUR PERIOD ON A WEEKDAY IN EACH OF FOUR SEASONS, (2) CLASSIFY VEHICLES DURING 16-HOUR PERIODS ON A WEEKDAY, SATURDAY AND SUNDAY IN EACH OF THE FOUR SEASONS, AND (3) COUNT TRAFFIC FOR SEVEN CONSECUTIVE DAYS IN EACH OF THE FOUR SEASONS TO PROVIDE AVERAGE DAILY TRAFFIC VOLUMES (ADT). THE PROCEDURES ARE SUMMARIZED FOR DETERMINING THE TOTAL NUMBER OF EQUIVALENT WHEEL LOADS OVER A SECTION SINCE CONSTRUCTION AND THE SUMMATION OF EQUIVALENT AXLE LOADS. CORRELATIONS WERE MADE BETWEEN EQUIVALENT AXLE LOADS AND (1) ADT, (2) HEAVY COMMERCIAL AVERAGE DAILY TRAFFIC (DCADT), AND (3) SUMMATION OF TYPES FOUR AND FIVE AXLE TRACTOR TRUCKS. IT IS SHOWN THAT EQUIVALENT LOADS CAN BE PREDICTED WITH INCREASING ACCURACY USING THESE PARAMETERS IN ORDER AS LISTED. THE ERRORS IN THESE PREDICTIONS ARE RELATED TO DESIGN THICKNESS. THE ANALYSES OF THE TRAFFIC STUDY WAS PROGRAMMED FOR THE 1604 COMPUTER. THE ESTIMATED YEARLY EQUIVALENT LOAD FOR THE LAST TWELVE YEARS WERE CONSIDERED TO TRY TO ESTIMATE THE PROBABLE FUTURE GROWTH OF TRAFFIC IN TERMS OF EQUIVALENT AXLE LOADS. THIS FACTOR IS NECESSARY FOR FUTURE DESIGNS TO HELP DETERMINE THE LOAD-LIFE OF THE PAVEMENT.

  • Supplemental Notes:
    • InvestigatiON 183, SPECIAL REPT 3, 60 PP, 15 FIG, 16 TAB,
  • Corporate Authors:

    University of Minnesota, Twin Cities

    Department of Civil Engineering, 500 Pillsbury Drive, SE
    Minneapolis, MN  United States  55455
  • Publication Date: 1967-3-13

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Filing Info

  • Accession Number: 00205511
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 20 1994 12:00AM