Finite-difference model for one-dimensional electro-osmotic consolidation

Abstract Small strain consolidation theories treat soil properties as being constant and uniform in the course of consolidation, which is not true in the case of electro-osmosis-induced consolidation practices. Electro-osmotic consolidation leads to large strain, which physically and electro-chemically affects to a non-negligible extent the nonlinear changes of the soil properties. For the nonlinear changes, iterative computations provide a mathematical approximation of the soil consolidation when the time steps and spatial geometry are intensively meshed. In this context, this paper presents a finite-difference model, EC1, for one-dimensional electro-osmotic consolidation, and this model is developed based on a fixed Eulerian co-ordinate system and uses a piecewise linear approximation. The model is able to account for the large-strain-induced nonlinear changes of the physical and electro-chemical properties in a compressible mass subjected to electro-osmotic consolidation and to predict the consolidation characteristics of the compressible mass. EC1 is verified against exact analytical solutions and test results obtained from an experimental program. Example problems are illustrated with respect to the numerical solutions of large-strain electro-osmotic consolidation.

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