Stress-Dilatancy for Soils. Part I: The Frictional State Theory

Abstract

An unconventional subdivision of volumetric strains, the newly formulated frictional and critical frictional states and some of energetic and stress condition assumptions result in new stress-plastic dilatancy relationships. These new stress-plastic dilatancy relationships are functions of the deformation mode and drainage conditions. The critical frictional state presented in this paper is a special case of the classical critical state.

Stress-Dilatancy for Soils. Part III: Experimental Validation for the Biaxial Condition

“…4). Contrary to the triaxial condition,   1 for granular soil in the plane strain condition [21]. This difference is perhaps due to a smaller degree of freedom for interparticle movement under plane strain than under triaxial conditions [1].…”

“…Thus, the values of In the frictional state theory, it is assumed that the angle  o is characteristic of soils and does not depend on the deformation mode [21]. For many noncohesive soils, it can be assumed that  o = υ c Φ [22].…”

“…This paper presents the validation of the general stress-dilatancy relationship developed by Szypcio [21] for plane strain conditions. Soil is treated as an isotropic continuum, and the rheology, breakage of grains, temperature changes and other non-mechanical effects are neglected.…”

“…Soil is treated as an isotropic continuum, and the rheology, breakage of grains, temperature changes and other non-mechanical effects are neglected. The influences of the intermediate stress ) ( 2   and non-coaxiality are analysed for drained and undrained conditions based on the frictional state theory [21] for experimental data presented in the literature. Only the pre-peak phase (stage), when the deformation is homogeneous, is analysed.…”

Rate effect on the shear resistance of sandy clay in direct shear tests

“…Almost in all tests the point at which stress ratio significantly changes was observed. Therefore, the Frictional State Theory (Szypcio, 2016(Szypcio, , 2017a used for the analysis gave new possibilities of direct shear tests results interpretation.…”