Modifying the NorSand soil model to improve static simple shear behaviour predictions

ABSTRACT: The simple shear laboratory test is nowadays commonly used to investigate soil behaviour under plain strain conditions of deformation. This article focusses on behaviour predictions of such laboratory test using the NorSand soil model. Through the analysis of various test predictions under undrained static simple shear conditions, it is shown that the original isotropic NorSand model is unable to correctly predict contractive behaviour observed in laboratory test results. By implementing the anisotropic critical state theory within the model to develop a new anisotropic NorSand model, the authors were able to satisfactorily predict sand behaviour under simple shear conditions. Prediction results obtained using the anisotropic NorSand model are consistently in better agreement with laboratory data than when using the original isotropic model, especially for anisotropically consolidated simple shear tests.