The paper investigates the mechanical behavior and anisotropic yielding of resedimented Nile silty clay (RNSC) in Egypt. The study uses samples resedimented in a consolidometer, and tested in a series of drained, stress controlled triaxial tests, where those samples are isotropically consolidated. The yield points measured show remaining asymmetry in the yield surface despite the isotropic consolidation. An asymmetric yield function is fitted to the yield data points using a modified stress tensor which accounts for the contacts between particles. The paper delineates the interaction between the inherent anisotropy, resulting from the resedimentation and the isotropic consolidation typically used in laboratory triaxial testing. Results indicate that the isotropic consolidation does not cause full rotation of the yield surface back to a symmetric state. The concept of local changes in the yield surface geometry around the consolidation path can explain the inconsistency between observed yield surface and the undrained stress path.
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