ABSTRACT
The inherent anisotropy showed by most natural clays, along with the time dependent phenomena of soft soils have practical consequences for i.e. the passive lateral thrust on piles.
This paper examines the anisotropic material response of soft soils resulting in transverse isotropy. Only one additional parameter is needed to describe this type of inherent elastic anisotropy. Among all strain amplitudes the strain rate dependency of clays is experimentally investigated. The effects are incorporated into the proposed model by an extension of the (hypo)elastic stiffness tensor and the incorporation of an additional strain mechanism depending on the material viscosity. The model is proposed under the platform of hypoplasticity, well-established for monotonic loading.
The proposed model is able to describe the material behavior of viscous and non-viscous soft soils, capturing also the inherent anisotropy of clays without imposing any restriction on the overconsolidation ratio. This is very interesting because the proposed model is able to simulate each effect without changing the model and keeping the same set of material parameters.
