Improvements of electroosmotic consolidation of soft clays by minimizing power loss at electrodes

Abstract

Although it appears promising in many laboratory studies, electroosmotic consolidation of soft clays is seldom used in practical applications. A study of well-documented case records of field applications illustrates the difficulty of transmitting the electrical potential to the soil deposit through the use of electrodes. An important amount of the electrical potential is indeed lost at the soil–electrode contact. The loss of potential at this point has been studied in a laboratory setup designed to reproduce the conditions existing in the field during electroosmotic consolidation. The laboratory results confirm that only about a third of the electrical potential applied at the electrodes is effectively transmitted to the soil and available for electroosmotic consolidation. Moreover, the laboratory studies have shown that a chemical treatment to increase the soil conductivity at the soil–electrode contact can double the electrical potential effectively transmitted to the soil and greatly improve the performance of electroosmotic consolidation.Key words: electroosmosis, soft clays, consolidation, potential loss, electrode treatment, soil improvement.