Electro-Osmotic Consolidation Experiments for Improvement of Soft Soils of Sarawak

An important priority for the Sarawak State of Malaysia is of providing road networks to enhance connectivity and economic development throughout the State. However, the more populated coastal areas along the South China Sea are covered by peat and other soft soil deposits. Construction of roads in such areas requires extensive ground improvement by preloading that is time consuming and at times also expensive. Electro-osmotic consolidation is a well known ground improvement technique for improvement of fine grained soft soils where a direct current introduced into the soil induces electro-osmotic flow of water from the anode to the cathode. Experiments were carried out in the laboratory to study the feasibility of electro-osmotic consolidation of an organic soil sample from North Sarawak. Commercially available prefabricated electric vertical drains were used as electrodes. This paper presents the experimental set-up, geotechnical characterization of the soil sample and the results of the tests conducted with incremental voltage gradient. Voltage and current were measured to assess the power consumption. The water content decreased and the shear strength increased significantly after 8 days of electrokinetic treatment. The results indicated a good potential for the application of electro-osmotic consolidation in organic soils.