Mechanics and thermodynamics of saturated/unsaturated porous materials and quantitative solutions*

Simulation of a fully coupled thermo–hydro–mechanical system in freezing and thawing rock

A coupled finite element model for the analysis of the deformation of elastoplastic porous media due to fluid and heat flow is presented. A displacement-pressure temperature formulation is used for this purpose. This formulation results in an unsymmetric coefficient matrix, even in the case of associated plasticity. A partitioned solution procedure is applied to restore the symmetry of the coefficient matrix. The partitioning procedure is an algebraic one which is carried out after integration in the time domain. For this integration, a two-point recurrence scheme is used. The finite element model is applied to the investigation of nonisothermal consolidation in various situations.

A coupled finite element model for the consolidation of nonisothermal elastoplastic porous media

The theoretical aspects of fully coupled thermohydromechanical behaviour of saturated porous media are presented. The non-linear behaviour of soil skeleton is assumed. A new concept called ‘thermal void ratio state surface’ is introduced to include thermal effects, and the stress state level influence on volume changes. The fluid phase flows according to Darcy's law and energy transport is assumed to follow Fourier's law classically. Variation of water permeability, water and solid unit weight due to thermal effects and pore pressure changes are included. A finite element package is developed based on final matrix form obtained from discretization of integral form of field equations by finite element method and integration in time. A very good agreement between the theoretical predictions and the experimental results was obtained for the several simple problems proposed by other authors. © 1997 by John Wiley & Sons, Ltd.

A formulation of fully coupled thermal–hydraulic–mechanical behaviour of saturated porous media—numerical approach

A VARIATIONAL PRINCIPLE EQUIVALENT TO THE GOVERNING EQUATIONS IN BIOT'S CONSOLIDATION THEORY IS DERIVED. ON THE BASIS OF THE VARIATIONAL PRINCIPLE, A NUMERICAL METHOD EFFECTIVE FOR NONHOMOGENEOUS, ANISOTROPIC SOILS IN ONE-, TWO-, OR THREE-DIMENSIONS IS DEVELOPED. TWO EXAMPLES ARE GIVEN TO ILLUSTRATE THE VALIDITY AND PRACTICALITY OF THE METHOD. /AUTHOR/

Finite element method applied to bilot's consolidation theory

In this paper, a general variational principle for the initial boundary value problem of quasi-static thermoelastic consolidation is developed by assuming infinitesimal deformation and an incompressible fluid flowing through a linearly elastic solid. By manipulating the coupling operators, an extended form of the variational pronciple is derved. The associated finite element formulation based on this principle is presented and numerical applications for plane strain thermo-elastic consolidation are revealed.

S. H. Advani

Papers

Variational principles and finite element simulations for thermo-elastic consolidation