Mixed experimental and numerical approach to evaluation
of material parameters of clayey soils
by
T. Janda, P. Kuklik and M. Sejnoha
Abstract
The present contribution reports on a mixed numerical experimental
study of the time dependent processes in saturated soils with
reference to isotropic consolidation. Owing to its relative
simplicity, the isotropic consolidation is often viewed as a basic
tool for inferring the material parameters of various constitutive
models. Within this modeling framework, the paper advocates the use
of critical state models for an accurate description of the time
dependent deformation of clayey soils. Material models, in which the
critical state model applies only to the subcritical region
are also addressed. Examples include models where the supercritical
region is cut off, e.g., by a Mohr-Coulomb surface.
Starting with the modified Cam clay model, as a classical
representative, the paper revisits a simple isotropic
consolidation test. It is suggested that such a conventional laboratory
experiment, when combined with a suitable optimization procedure, is
sufficient in deriving the desired material parameters, including
the initial void ratio, deformation dependent variation of the coefficient
of permeability and the preconsolidation pressure representing here
an important measure of the structural strength of soils.
Several numerical and experimental results are
presented to support the theoretical grounds.
Last modified: Dec 12 2001