Experimental Study On Electro-osmotic Consolidation Of Soft Clay Using EKG Electrodes

As a new kind of geosynthetics, Electrokinetic Geosynthetics (EKGs) incorporates electro-osmosis phenomena with the existing traditional functions of geosynthetics, and can be used in civil engineering such as consolidation and soil reinforcement. For fine grain soil, it' s very difficult, sometimes imposible, to drain the pore water. It will be efficient to use electro-osmosis in this instance. It had conquered the disadvantages of traditional electrode material using EKG, such as: never electro-corrupt, convenience in polarity reversal. So it' s very significant for the research of EKGs.Based on the formers' studies, further research is done in this paper on the mechanism and the process of electro-osmosis and theory of electro-osmosis consolidation. It is also presented that EKGs can make up for the disadvantages of traditional electro-osmosis, so it will make great progress to put EKGs into the ground improvement.A laboratory testing program was conducted on soft clay using EKGs and geotextiles electrodes. The sample was consolidated under the electric field of 40V for 480 hours (20 days). The voltage gradient, current density, suction and settlement curves of different levels in the sample were measured. The water content, shear strength and consolidation curve of the samples after consolidation were compared with the initial indexes. The electrodes were not corrupted afer the test. The result demonstrated the efficiency of the EKG electrodes as well as the advantage and disadvantage compared with the traditional materials.Further analysis was done on the theory of interface electric resistance of electro-osmosis consolidation. The design formula and corresponding program were also provided.Useful conclusions were given to the further improvement on the EKG material. The direction of further research was discussed in the end of this paper.