On the dewatering of electroosmotic soil using intermittent current incorporated with calcium chloride

Although electroosmosis has been confirmed to be a promising technique for stabilizing soil with low permeability and high water content, several issues remain with this innovative method, including high power consumption, nonuniform strengthening effect, and electrode corrosion. In this context, for improving the feasibility of electroosmosis, a set of comparison laboratory tests were performed in customized apparatus to investigate the efficiency of intermittent current for the dewatering and consolidation of silty clay in the presence of calcium chloride. In this study, the time intervals of 0, 1, 2, 4, 8 h were, respectively, combined with 15% calcium chloride solution during the process of electric treatment. By comparison with conventional electroosmosis, the test results apparently indicated that intermittent current incorporated with calcium chloride not only increased the undrained shear strength of soil matrix, but also reduced the anode corrosion and power consumption induced by the injection of CaCl2 solution, which made the process economically feasible in practical projects.