To enhance effect of electroosmostic improvement and to shorten the time of treatment, this research made use of interaction between chemical solution and soil particles under the influence of electric field, such as cation exchange, water adsorption, and particle cementation. The elctroosmostic method with the injection of saline solution was developed in this study. The results of this research showed that using the electroosmostic treatment with the injection of calcium chloride (CaCl2) treatment for a period of 9 days, the undrained shear strength of soil increased averagely by 350% compared to the initial strength and 120% compared to electroosmostic treatment without the injection of saline solution. However, after the electroosmostic treatment with the injection of calcium chloride (CaCl2) treatment for a period of 1 day, the undrained shear strength of soil near anode is 1.36 times compared to electroosmostic treatment without the injection of saline solution treated for a duration of 9 days. The elctroosmostic method with the injection of saline solution can certainly enhance electroosmostic effect of improvement and shorten the time of treatment.
When an electric potential is applied across a wet soil mass, cations of double layer in a soil would be attracted to the cathode and anions to the anode. As these cations migrate to the cathode, they drag water with them. Because there are more cations than anions in a soil containing negatively charged clay particles, there is a net flow of water towards the cathode. This flow is called electroosmosis. The field application of the electroosmosis in silts, silt clays, and soft sensitive clay successfully was demonstrated (Casagrande, 1961; Bjerrum, 1967; Fetzer, 1967 and Lo, 1991b) and then some investigators continually proceeded with laboratory treatment to explore ground improvement by electroosmosis, as shown in Table 1.