Influence of anisotropic small strain stiffness on the deformation behavior of geotechnical structures

Constitutive models based on the multilaminate framework naturally account for strain-induced anisotropy, but inherent anisotropy needs additional considerations. A recently introduced feature is the capability of the model to take into account anisotropic elasticity in the small strain range. The implications of taking into account anisotropy of small strain stiffness for the analysis of geotechnical problems is addressed in this paper by solving two relatively simple benchmark problems: a deep excavation and a strip footing. It follows from these studies that, if displacements and thus strains remain moderate (which is often the case for these types of problems), the influence of small strain stiffness anisotropy is more pronounced compared with problems where relatively large strains occur. However, the influence of stiffness anisotropy can be approximately accounted for by using the average of the axial stiffnesses.