Influence of Soluble Salt on Electro-Osmotic Consolidation of Soft Clay

Abstract

A series of electro-osmotic consolidation laboratory tests was conducted to investigate the influence of soluble salt on the electro-osmotic consolidation of soft clay. Remolded soil samples with different salinities of KCl, NaCl, and CaCl₂ were tested in the modified electro-osmosis oedometer experimental system. Final water content, vane shear strength, and pH value of test soil samples were analyzed by monitoring the changes in the electric current, volume of drainage, and vertical settlement during the tests. The results showed that addition of soluble salts can improve the electro-osmotic consolidation of soft clay. However, excessive salinity will reduce the efficiency of electro-osmotic consolidation. The optimal salinity of the soluble salt was determined for each type of salt. Moreover, an improved consolidation efficiency can be achieved by using CaCl₂ rather than KCl or NaCl.