A new constitutive model for time-dependent behaviour of soft soils has been recently proposed.Stemming from a previously developed viscoelastic isotropic model based on ellipses of Modified Cam Clay,anisotropy was taken into account by introducing a fabric tensor to represent the rotation of the constitutiveellipses in p'-q (mean effective stress- deviatoric stress) plane. Moreover, a rotational hardening law describesthe evolution of anisotropy due to volumetric and deviatoric creep strain rates. Due to the particle orientationinduced by deposition mechanism, natural soils are anisotropic in terms of strength and stiffness. The improve-ment induced by the new formulation is particularly evident in stress paths in extension. The new soil constantsrequired by the anisotropic formulation need no calibration, since they can be expressed in terms of parametersalready used in the isotropic model and familiar to practicing geotechnical engineers. In this paper, the numeri-cal analysis of an embankment on soft soils has been carried out, in order to investigate on the differences interms of predictions of vertical and horizontal displacements between the isotropic and the anisotropic creepmodel.
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