The Relationship between the Shear Strength of Sands in Triaxial Compression, Plane Strain and Direct Shear

Synopsis A theoretical relation is derived between the peak Coulomb φ values for saturated drained sands measured in the direct shear test and the plane strain compression test using the stress-dilatancy equation and the assumption that the directions of principal strain increment and principal stress coincide. Limiting dilatancy rates in triaxial compression allow an overall comparison of the φ values to be expected in these three types of test. Present available experimental data indicate quite close agreement over the range φu = 17°–39° for cohesion-less soils. On derive une relation theorique entre les valeurs φ de pointe de Coulomb pour des sables draines satures mesurees dans l'essai de cisaillement direct et l'essai de compression a deformation en plan en utilisant 1'equation de contrainte-dilatabilite et la supposition que les directions de l'accroissement de deformation principale et de la contrainte principale coincident. Des taux limites de dilatabilite en compression tr axiale permettent de fa...