AN INVESTIGATION OF THE PERMEABILITY OF ASPHALT MIXES

A PROCEDURE WAS DEVELOPED FOR MEASURING THE AIR PERMEABILITY OF VARIOUS SPECIMENS OF COMPACTED ASPHALT. A METHOD OF DETECTING ANY ACCIDENTAL CHANGES IN THE COMPOSITION OF A MIXTURE PRODUCED BY AN ASPHALT PLANT, SOON AFTER MANUFACTURE OF THE MATERIAL, USING THE AIR PERMEABILITY APPARATUS, IS SUGGESTED. SPECIMENS OF ASPHALTIC CONCRETE CONFORMING TO THE REQUIREMENTS OF THE ONTARIO DEPARTMENT OF HIGHWAYS FOR SURFACE COURSE MIXTURES WAS PREPARED BY THE MARSHALL METHOD AND TESTED IN THE AIR PERMEABILITY APPARATUS. THE VOID CONTENT WAS MEASURED AND RELATIONSHIPS ESTABLISHED BETWEEN PERMEABILITY AND VOID CONTENT. A MARKED DECREASE IN PERMEABILITY OCCURRED BELOW A VOID CONTENT OF ABOUT 5 PERCENT FOR ALL MIXTURES TESTED. THE EFFECTS OF COMPACTED EFFORT, ASPHALT CONTENT AND AGGREGATE GRADATION ON PERMEABILITY AND VOID CONTENT WERE TESTED. SEVERAL DRY AGGREGATE BLENDS WERE TESTED IN THE AIR PERMEABILITY APPARATUS AND THE EXPERIMENTAL PERMEABILITIES OBTAINED WERE COMPARED WITH VALUES CALCULATED BY MEANS OF THE KOZENY EQUATION USING THE SPECIFIC SURFACE CALCULATED FROM THE GRAIN SIZE DISTRIBUTION AND AN APPROPRIATE SHAPE FACTOR. GOOD AGREEMENT IN THE VALUES WAS OBTAINED WHEN THE VARIATION IN PARTICLE SIZE WAS NOT TOO GREAT. /CGRA/

  • Supplemental Notes:
    • 27 Pp, 15 FIG, 3 TAB, 3 PHOT, 13 REF, 2 APP
  • Corporate Authors:

    Ontario Department of Highways

    1201 Wilson Avenue
    Toronto, Ontario M3M 1J8,   Canada 
  • Authors:
    • Davies, J R
    • Walker, R N
  • Publication Date: 1969-5

Subject/Index Terms

Filing Info

  • Accession Number: 00210582
  • Record Type: Publication
  • Source Agency: CANADIAN GOOD ROADS ASSOCIATION
  • Files: TRIS
  • Created Date: Apr 20 1970 12:00AM