STRENGTH BEHAVIOR OF SELECTED ASPHALT-AGGREGATE SYSTEMS IN TRIAXIAL COMPRESSION

SOME OF THE BASIC COMPOSITIONAL AND ENVIRONMENTAL FACTORS INFLUENCING THE STRENGTH BEHAVIOR OF ASPHALT-AGGREGATE ARE ISOLATED AND STUDIED USING CONSOLIDATED-DRAINED AND CONSOLIDATED-UNDRAINED TRIAXIAL COMPRESSION TESTS. THESE FACTORS INCLUDE ASPHALT CONTENT, AGGREGATE GRAIN SIZE AND DISTRIBUTION, AGGREGATE DENSITY, RATE OF STRAIN, TEMPERATURE, AND VOLUME CHANGE DURING SHEAR. THE RESULTS OF THIS INVESTIGATION SHOW THAT: (1) THE ADDITION OF ASPHALT TO A COHESIONLESS AGGREAGTE SYSTEM CAUSES IT TO EXHIBIT AN EFFECTIVE COHESION INTERCEPT AT FAILURE DUE TO THE VISCOUS NATURE OF THE ASPHALT. HOWEVER, ITS EFFECTIVE ANGLE OF INTERNAL FRICTION (DETERMINED BY THE MOHR-COULOMB CRITERION OF FAILURE) IS CONSIDERABLY REDUCED DUE TO THE LUBRICATING EFFECT OF THE ASPHALT, (2) THE EFFECTIVE COHESION IS A FUNCTION OF STRAIN ENERGY STORED IN THE ASPHALT BINDER DURING SHEAR. THE ENERGY STORAGE, AND THEREFORE THE EFFECTIVE COHESION, INCREASES WITH INCREASING STRAIN RATE, DECREASING TEMPERATURE, AND INCREASING AMOUNT OF ASPHALT UNDERGOING STRAIN, (3) THE EFFECTIVE FRICTION ANGLE INCREASES ONLY WHEN THE LUBRICATION QUALITIES OF THE ASPHALT DECREASE, DUE TO EITHER HIGH TEMPERATURES OR VERY LOW ASPHALT CONTENTS, AND (4) RESTRICTING SAMPLE VOLUME CHANGE DURING SHEAR HAS NO EFFECT ON THE MOHR-COULOMB STRENGTH PARAMETERS, BUT CAN RESULT IN A LARGE INCREASE IN STRENGTH IF THE SAMPLE HAS A TENDENCY TO DILATE DURING SHEAR. /AUHTOR/

  • Supplemental Notes:
    • Hpr-1/2/, 6, STATE NO R11-1
  • Corporate Authors:

    Massachusetts Institute of Technology

    Department of Civil Engineering, 77 Massachusetts Avenue
    Cambridge, MA  United States  02139
  • Authors:
    • Wissa, A
    • Blouin, S
  • Publication Date: 1967-6

Subject/Index Terms

Filing Info

  • Accession Number: 00210383
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS
  • Created Date: Dec 15 1994 12:00AM