Numerical modelling of electro-osmosis consolidation of unsaturated clay at large strain

摘要

In this paper a numerical model of electro-osmosis consolidation of unsaturated clay in a multidimensional domain is presented, with the coupling of soil mechanical behaviour, pore water transport and electric field at large strain being considered. In particular, the flow and deformation characteristics of the coupled electro-osmosis consolidation system in the unsaturated condition, caused by negative pore water pressures developed near the anode, are emphasized. Under unsaturated conditions, all transport parameters involved in electro-osmosis consolidation are highly dependent on the degree of water saturation. Three fully coupled governing equations are presented and solved using the finite element method. In order to illustrate the accuracy of the formulation, the sand column desaturation test performed by Liakopoulos (1965) is simulated first. The performance of the proposed algorithm in modelling the electro-osmosis consolidation of unsaturated clay at large strain is then demonstrated for the fully coupled analysis of a one dimensional numerical example. The numerical results indicate that consideration of the unsaturated condition is important.