Modeling of soil cracks in electroosmosis

Abstract

Electroosmosis is a dewatering technique for fine-grained soils that, by means of an electric current passing through a series of electrodes, moves a volume of pore water from the anodes toward the cathodes. The dewatering process can effectively reduce the soil water content but often results in the formation of surface cracks. The cracks collectively reduce the passage of the electric current, thereby diminishing the dewatering efficiency. To optimize dewatering, crack formation must be studied. A numerical model to predict soil cracks formed during the electroosmosis dewatering process is developed in this paper. This model considers the unsaturated conditions during dewatering and combines the constitutive surface of unsaturated soils with the Mohr–Coulomb failure envelope to determine cracking. This model also accounts for the nonlinear variations in soil properties, the degree of saturation, and cracking. This model is validated against laboratory test results and is applied to various example problems. The research outcomes result in the assessment of crack evolution and the identification of factors that affect crack development.