Numerical model for electro-osmotic drainage in unsaturated soils

Abstract

A numerical model coupling of water flow and electrical transport in a deformable porous medium is developed to simulate the electroosmosis drainage in the unsaturated soil. This model is in accounting for unsaturated-induced nonlinear changes in the physical and geoelectrical properties that take place on the soil, with the additions of two-dimensional consolidation, and an external hydraulic gradient. The exponential relation is used to represent nonlinear changes in the hydraulic and electro-osmotic conductivities, and soil-water retention curve. The algorithm of this model is conducted using finite-element method. The pore water pressure, settlement, moisture content, drainage, and electric potential and current density as a function of time and position within the soil can be obtained. Finally, the proposed numerical solution is verified to be accurate compared with the experimental measurement.