This paper presents the results of a laboratory study concerning the effects of the geometric characteristics of coarse aggregates on the strength characteristics of soil-aggregate mixtures. These geometric characteristics were determined by the particle-index test, developed at the University of Illinois particularly for this purpose. A total of five coarse-aggregate materials with discernible geometric characteristics, including pit-run gravel, crushed stone, and mine-chat materials, were used. Each coarse aggregate was combined with various percentages of finer aggregate and soil materials to form three different gradations. The strength characteristics of these mixtures were determined by drained triaxial compression tests. Each mixture was tested at its maximum density and optimum moisture content, as determined according to AASHO Designation: T-99-57. The results of this investigation show that the maximum principal stress difference in the soil-aggregate mixtures increases, at all confining pressures, with increasing particle index of the coarse aggregates. The effect of the particle index of aggregates on the stress difference appears greater for greater confining pressures and increases amounts of coarse aggregates in the mixture. The data also reveal that an almost linear relationship exists between the angles of shearing resistance of the soil-aggregate mixtures and the particle index of the coarse aggregates contained in the mixtures. The conclusion that the strength characteristics of a soil-aggregate fraction appears to be deserving of some consideration in the design of mixtures for resistance displacement.

  • Supplemental Notes:
    • Prepared in cooperation with the State of Illinois, Division of Highways, and the U.S. Department of Public Roads.
  • Corporate Authors:

    University of Illinois, Urbana-Champaign

    Department of Civil and Environmental Engineering
    205 North Mathews Avenue
    Urbana, IL  United States  61801-2352
  • Authors:
    • Huang, E Y
    • Auer, A
    • Triffo, R P
  • Publication Date: 1965-1

Media Info

  • Features: Figures; Tables;
  • Pagination: p. 922-933

Subject/Index Terms

Filing Info

  • Accession Number: 00263886
  • Record Type: Publication
  • Report/Paper Numbers: Hwy Eng Series No 15
  • Files: TRIS
  • Created Date: Dec 19 1974 12:00AM