Authors:
Zhiyi Liu; Yu Song; Fengxi Zhou; Liye Wang;
Abstract:
To explore the deformation behavior and failure strength of sulfate saline silty clay at a temperature of -10 ℃; and confining pressures 6 -10 MPa, we have performed low-temperature triaxial shear tests on sulfate saline silty clay in Hexi region of Gansu Province;the variation trend of deviatoric stress, volumetric strain, and initial deformation modulus with confining pressure were analyzed. The results demonstrated that the stress-strain curve of frozen sulfate saline silty clay was hyperbolic, the deviatoric stress increased as the axial strain increased and eventually constant. Owing to particle breakage and melting of ice, when the confining pressure, the strength decreased as the confining pressure increased, and the sample exhibited volumetric shrinkage throughout the entire confining pressure range. A constitutive model of frozen sulfate saline silty clay under high confining pressure has been proposed in combination with the Duncan-Chang model, and the validity of the model has been confirmed by comparison with test data.
Keywords:
Frozen sulfate saline soils, Strain hardening, Volumetric contraction, Strength criterion, Triaxial compression tests.