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

Abstract

An important priority for the Sarawak State of Malaysia is ofproviding road networks to enhance connectivity and economic developmentthroughout the State. However, the more populated coastal areas along the SouthChina Sea are covered by peat and other soft soil deposits. Construction of roads insuch areas requires extensive ground improvement by preloading that is timeconsuming and at times also expensive. Electro-osmotic consolidation is a wellknown ground improvement technique for improvement of fine grained soft soilswhere a direct current introduced into the soil induces electro-osmotic flow of waterfrom the anode to the cathode. Experiments were carried out in the laboratory to studythe feasibility of electro-osmotic consolidation of an organic soil sample from NorthSarawak. Commercially available prefabricated electric vertical drains were used aselectrodes. This paper presents the experimental set-up, geotechnical characterizationof the soil sample and the results of the tests conducted with incremental voltagegradient. Voltage and current were measured to assess the power consumption. Thewater content decreased and the shear strength increased significantly after 8 days ofelectrokinetic treatment. The results indicated a good potential for the application ofelectro-osmotic consolidation in organic soils.