Study on Stress–Strain Relation of Lime-Treated Weathered Red Sandstone Soil

Abstract

In this work, a series of triaxial consolidated drained shear tests were used to investigate the stress–strain relationships of weathered red sandstone soil and lime-treated weathered red sandstone soil. Firstly, the triaxial consolidated drained shear test results were used to analyze the relationship between deviatoric stress $q$, axial strain ${\varepsilon }_{1}$, shear strain ${\varepsilon }_{\mathrm{s}}$, and volume strain ${\varepsilon }_{\mathrm{v}}$. Secondly, the yield surface of the soil was divided into the volume yield surface and shear yield surface, and two yield surfaces were assumed as ellipse and parabola, respectively. The ellipse volume yield surface and the parabola shear yield surface were fitted based on ${\varepsilon }_{\mathrm{v}}-{\varepsilon }_{1}$, $q-{\varepsilon }_{\mathrm{s}}$ test results, respectively. Finally, based on the ellipse-parabola constitutive model, the elastoplastic constitutive equations with double yield surfaces of weathered red sandstone soil and lime-treated weathered red sandstone soil were constructed. This provides a basis for the numerical analysis of the deformation of red sandstone weathered soil and lime-treated red sandstone weathered soil.