ROADWAY FAILURE STUDY NO. II - LATERAL CRACKING OF ASPHALTIC CONCRETE

THE RELATIONSHIP WAS EXAMINED OF ASPHALT AGING TO THE ALTERNATION OF MIX PROPERTIES AND TO THE VARIATION IN FREQUENCY OF LATERAL CRACKING OF ASPHALTIC CONCRETE PAVEMENTS. TEMPERATURE RECORDS WERE MADE AT THREE FIELD TEST SITES DURING THE WINTER MONTHS. BASED ON THE 2-INCH PAVEMENT THICKNESS, TEMPERATURE DIFFERENTIALS OF 11 DEGREES PER INCH OF PAVEMENT THICKNESS WERE OBSERVED. EXPANSION AND CONTRACTION MEASUREMENTS WERE MADE ON REFERENCE POINTS AT ARTIFICIAL JOINTS AND IN UNCRACKED AREAS. A CORRESPONDENCE OF CRACK WIDTH INCREASE WAS NOTED WITH A DECREASE OF PAVEMENT TEMPERATURE. SUBGRADE FRICTION TESTS WERE CONDUCTED BY MEASURING THE HORIZONTAL FORCE NECESSARY TO CAUSE MOVEMENT OF THE PAVEMENT ON THE SUBGRADE. INITIAL AND AGED PAVEMENT SAMPLES AND SAMPLES FROM CRACKED AND UNCRACKED AREAS WERE TESTED IN THE LABORATORY FOR ELASTIC MODULUS AND ULTIMATE STRENGTH IN TENSION AND FOR LINEAR COEFFICIENT OF EXPANSION. THE EXPANSION COEFFICIENTS WERE FOUND TO BE HIGHER ABOVE 0 F THAN BELOW. THE CHARACTERISTICS OF MIXTURES AND ASPHALTS RECOVERED FROM PAVEMENTS AFTER VARYING SERVICE PERIODS WAS DETERMINED IN THE LABORATORY. AGING OF ASPHALTS WAS DETERMINED BY CHANGES IN PENETRATION AND SOFTENING POINT AND BY INVERSE GAS-LIQUID CHROMATOGRAPHY. CHANGES IN ASPHALT COMPOSITION WITH INCREASING AGE WERE NOTED ON SAMPLES FROM AREAS WITH LATERAL CRACKING. INCREASED HARDENING OF ASPHALTS WAS OBSERVED FOR PAVEMENT SAMPLES WITH HIGH AIR VOID CONTENTS. DIFFERENCES IN PERFORMANCE COULD BE RELATED TO ASPHALT STIFFNESS AND FILLER CONCENTRATION. FOR PROJECTING LOW-TEMPERATURE BEHAVIOR, THE PENETRATION AND SOFTENING POINT TESTS WERE FOUND TO BE MORE INDICATIVE THAN VISCOSITY TESTS. A PREMIXING OF ASPHALT WITH FILLER, FOLLOWED BY THE ADDITION OF THE REMAINING AGGREGATE, PRODUCED MIXTURES WITH HIGHER MARSHALL STABILITIES THAN WHEN MIXED IN THE CONVENTIONAL MANNER. PLATE THERMAL STRESSES AND THERMAL WARPING STRESSES WERE ANALYZED USING WESTERGAARD EXPRESSIONS AND A COMPUTER SOLUTION.

  • Supplemental Notes:
    • Hpr-1/3/, BPR-7
  • Corporate Authors:

    University of Wyoming, Laramie

    Wyoming Survey and Analysis Center, 710 Garfield
    Laramie, WY  USA  82070

    Bureau of Public Roads /US

    400 7th Street, SW
    Washington, DC  USA  20590
  • Authors:
    • Lamb, D R
    • SCOTT, W G
    • Gietz, R H
    • Armijo, J D
  • Publication Date: 1967-8

Subject/Index Terms

Filing Info

  • Accession Number: 00210386
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS
  • Created Date: Jan 16 1994 12:00AM