Porosity (or void ratio) is one of the most important index measures of granular materials. It alone is not, however, enough for a reasonably complete description of the basic properties of materials of this kind. The fabric ellipsoid appears to be a good second index measure. It is closely related to the probability density function e(alpha, beta) which defines the angular distribution of the contact normals. Based on experimental evidence the following is concluded. The fabric ellipsoid is closely related to the stress ellipsoid and characterizes a second-order tensor with a clear physical meaning; the principal axes of the fabric ellipsoid seem to tend toward those of the stress ellipsoid and this appears to hold whether the principal stress axes rotate gradually or discontinuously during a course of deformation; and there seems to exist a quantitative relation between the fabric ellipsoid and the overall applied stresses, especially in the post-failure states. It appears that the function e(alpha, beta) continuously changes in a manner so as to increase the ability of the material to withstand the increased applied stresses. The changes of the fabric, characterized by the changes of e(alpha, beta) result in the hardening (or softening) of the granular materials in a given deformation course. (Author/TRRL)

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 479-495
  • Serial:
    • Volume: 30
    • Issue Number: 4
    • Publisher: Thomas Telford Limited
    • ISSN: 0016-8505

Subject/Index Terms

Filing Info

  • Accession Number: 00330854
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Aug 15 1981 12:00AM