A triphasic model for unsaturated soil based on the theory of porous media

✍ Scribed by W. Ehlers; P. Blome

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 664 KB
• Volume: 37
• Category: Article
• ISSN: 0895-7177
• DOI: 10.1016/s0895-7177(03)00043-8

✦ Synopsis

In the present contribution, the formulation of the governing equations of coupled flow and deformation processes in saturated and unsaturated soils is based on the well-founded theory of porous media (TPM). Embedded in this concept, the model under consideration represents a triphasic medium of a cohesivefrictional elsstoplastic solid skeleton and a binary pore-fluid, which is composed of a materially incompressible liquid (wetting phase) and a materially compressible gas (nonwetting phase). The unsaturated domain (saturation in terms of liquid saturation) of the porous medium is included in the model by the application of a capillary-pressure-saturation relation, which takes into account the interaction of the solid skeleton and the two pore-fluids. Furthermore, the interaction is described by Darcy's filter law including a relative permeability, which depends on the deformation of the pore space and the degree of saturation. Finally, a corresponding finite element formulation is presented and applied to a volumetrically strongly coupled solid-fluid-problem.