Stabilisation of Soft Soil Using Electrokinetic

Abstract—This paper presents an experimental study on applying Electrokinetic Stabilisation (EKS) method to stabilise soft soil which has low shear strength. EKS method is the combination processes of electroosmosis and chemical grouting. This technique is most effective in silty and clayey soils where the hydraulic conductivity is very low. Soil sample was dried, ground and sieved. Water was added to the sample to form slurry. The slurry was then inserted to the EKS test rig where a load was applied to it until the slurry become saturated. Once saturated, EKS treatment was carried out to it where the electrolyte used was calcium chloride (CaCl2) and Ferrum plate was used as electrodes. After 7 days of EKS treatment, the treated soil was then investigated through their physical and chemical properties. It was found that the treated soil near the cathode has the highest shear strength value up to 18.06 kN/m2 compared with the anode and in the middle of the soil sample. From consolidation results, the data is useful in determining the compression index Cc, coefficient of consolidation cv and volume of compressibility mv. It shows that after EKS treatment the pH of the sample was increased near the cathode, while the electric conductivity value decreased near the cathode. It shows that the concentration of Ca2+ increased near the anode and Fe3+ increased near the cathode, obtained from atomic absorption spectrometer testing. Nevertheless, there’s no new minerals presences after the EKS treatment and the three major elements in clay are silicate oxide, aluminum oxide and ferum oxide. Keywords-Electrokinetic stabilisation; electroosmosis; chemical grouting; clayey soils; shear strength. I