FINITE ELEMENT ANALYSIS OF IMMEDIATE AND CONSOLIDATION DEFORMATIONS BASED ON EFFECTIVE STRESS PRINCIPLE

Abstract

Elastic and elastic-plastic problems in soil mechanics have been frequently analysed numerically by the finite element method. Most of the problems were analysed in terms of total stress and a few in terms of effective stress and pore water pressure. The aim of this study is to obtain the accurate solutions of immediate and consolidation deformations of anisotropic and heterogeneous poro-elastic media introducing the concept of effective stress by the finite element technique.Firstly, this paper describes the principle of the finite element method in the problem of consolidation accompanying with undrained deformation and the procedure of analysis. It is especially emphasized that the interpolation functions for the pore water pressure must be quadratic in space and those for the displacement must be cubic. Secondly, the deformation and the distributions of the pore water pressure or the stresses in the isotropically homogeneous and elastic foundation layer just after the application of a uniform strip load and during the consolidation process are computed as an example. The superiority of the numerical technique is ascertained by comparing the results with those based on total stress analysis.