SIGNIFICANCE OF CYCLIC CONFINING STRESS IN REPEATED-LOAD TRIAXIAL TESTING OF GRANULAR MATERIAL

A number of research projects have been concerned with determining the nonlinear stress-strain characteristics of granular materials by using repeated-load triaxial tests. Improvements in materials testing equipment have lead to experiments in which the confining stress and the vertical stress were applied cyclically. There is an apparent difference in the resilient Poisson's ration determined under constant and under variable confining stresses. This difference is best explained by considering the behavior of granular materials in terms of volumetric stress-strain and shear stress-strain relationships. By doing this, one can show that Poisson's ratio is a function of the ratio of volumetric strain to shear strain. Resilient strains were investigated separetely from permanent strain because the permanent strain developed depended on the loading history of the sample and because the resilient behavior was not affected by any previous subfailure stress applications. To keep materials testing techniques simple, a constant confining stress equal to the mean value of a cyclic confining stress can be considered to be equal to the cyclic confining stress for determining the resilient modulus and permanent deformation.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 49-58
  • Monograph Title: Pavement and soil characteristics
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00126819
  • Record Type: Publication
  • ISBN: 0309023882
  • Files: TRIS, TRB
  • Created Date: Dec 16 1975 12:00AM