EFFECT OF AGGREGATE SHAPE ON BITUMINOUS MIX CHARACTER

Details are described of on effort to determine if shape of aggregate is of significance in the use of bituminous paving material. Three tons of trap rock were passed through a 3-inch laboratory crusher and all particles were placed in one of 3 shape categories. The factors investigated were stability, voids, density, required asphalt content and durability. Bulk density was found by "weight of sample in water". Stability tests followed ASTM D1560 with minor timing adjustments. Samples were tested for stability at an age of 24 hours. It is concluded, on the basis of the study, that the effect of shapes on density is not large; voids decrease with increasing asphalt; void ratio for blends of at least 2 shapes tends to be lower than for one shape alone; and increases in asphalt above 6 percent cause large reductions in stability unless the aggregate is a blend of shapes approaching 50 regular.

  • Supplemental Notes:
    • This research was sponsored by the Joint Highway Research Advisory Council of the University of Connecticut and the Connecticut Department of Transportation.
  • Corporate Authors:

    University of Connecticut, Storrs

    Department of Civil and Environmental Engineering, 261 Glenbrook Road
    Storrs, CT  United States  06269-2037
  • Authors:
    • Stephens, J E
  • Publication Date: 1974-12

Media Info

  • Features: Figures;
  • Pagination: 32 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00096475
  • Record Type: Publication
  • Report/Paper Numbers: JHR 74-87 Final Rpt.
  • Files: TRIS
  • Created Date: Aug 13 1975 12:00AM