THEORETICAL ASPHALTIC CONCRETE EQUIVALENCES

THEORETICAL ASPHALTIC CONCRETE EQUIVALENCES WERE CALCULATED ON A CONTINUOUS HOURLY OR FOURTH HOURLY BASIS FOR A 245-DAY PERIOD. FOR THESE CALCULATIONS EQUIVALENCE WAS DEFINED AS THAT THICKNESS OF BASE NECESSARY TO REPLACE ONE INCH OF SURFACING FOR EQUAL DEFLECTION. DEFLECTIONS WERE CALCULATED USING THE LAYER ELASTIC THEORY AND THE RESULTS OF STATIC AND DYNAMIC LAB TESTS OF THE PAVEMENT MATERIALS IN THE FREQUENCY DOMAIN. THE MATERIALS INVESTIGATED WERE TWO ASPHALTIC CONCRETE SURFACINGS AND THREE ASPHALTIC CONCRETE BASES. THE EFFECT OF TESTING SPECIMENS WITH H/D RATIOS OF LESS THAN TWO WAS INVESTIGATED. THE SUB-GRADE WAS THAT DETERMINED FROM THE 1960 TRENCHINGS AT THE AASHO ROAD TEST AND THE CONTINUOUS HOURLY TEMPERATURE DATA WERE THOSE REPORTED BY THE ASPHALT INSTITUTE. CONTINUOUS 19-KIP SINGLE-AXLE LOADINGS MOVING AT 50 MPH WERE ASSUMED FOR THE PRINCIPAL CALCULATIONS. THE EFFECTS OF DIFFERENT LOADINGS WERE EXAMINED AS FUNCTIONS OF WEIGHT, SPEED, TIME, AND CONTACT AREA TOGETHER WITH THE EFFECTS OF DIFFERENT SUBGRADES AND LAYER THICKNESSES. IT WAS CONCLUDED THAT THERE IS NO UNIQUE EQUIVALENCE AND THAT THE INCLUSION OF A FAILURE TERM IS NECESSARY TO THE THEORETICAL CALCULATION OF EQUIVALENCE FOR GIVEN MATERIALS, ENVIRONMENT AND LOADINGS. /AUTHOR/

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/hrr/1968/239/239-005.pdf
• Supplemental Notes:
  • 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:
  • Coffman, Bonner S
  • Ilves, George
  • Edwards, William
• Publication Date: 1968

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 95-119
• Monograph Title: Design and performance of pavement systems
• Serial:
  • Highway Research Record
  • Issue Number: 239
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Asphalt concrete; Axle load force; Base course (Pavements); Calculation; Deflection; Dynamic tests; Elasticity (Mechanics); Materials tests; Pavement layers; Static tests; Surface course (Pavements); Theory; Thickness
• Uncontrolled Terms: Computation
• Old TRIS Terms: Elastic theory; Thickness design
• Subject Areas: Highways; Pavements;

Filing Info

• Accession Number: 00205732
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Jan 31 1994 12:00AM