Ductile compressive failure of columnar saline ice under triaxial loading

Experiments and analysis have shown that the ductile compressive yield stress (at -10 degrees C at 4 x 10(-5) s(-1)) of S2 saline ice, an orthotropic material whose crystallographic c axes are randomly oriented in the plane perpendicular to the long axis of the columnar grains [Michel, 1978], loaded triaxially both across and along the columnar-shaped grains obeys Hill's [1950] criterion under low to intermediate levels of confinement. Correspondingly, the ratio of inelastic strains can be described by the attendant associated flow rule.