ANISOFT – Constitutive Model for Undrained Loading of Anisotropic and Strain-Softening Clay

An elastoplastic constitutive model is presented. The model is developed in order to study the effects of anisotropy and post-peak softening in problems of saturated clay subjected to monotonic undrained loading. The non-linear stress-strain relationship depends on the orientation of the major principal stress relative to the vertical. The model is demonstrated by simulation of an undrained simple shear deformation where the direction of the principal stresses rotates.