Electrokinetic Stabilization of an Illitic Clay

Remolded illitic clay cylindrical samples, 2-l/2-in. and 5-in. long, were treated electrokinetically for periods of between 8 hr and 11 days. Treatment occurred in the presence of a large supply of calcium ions at the anode. Measurements wore obtained of the vane shear strength of the soil before and after treatment. When corrected for water content changes, these data lead to the conclusion that essentially no chemical cementation had occurred. It appeared that soil hardening was the result of decreases in the water content of the soil and of physical-chemical changes in the soil. The physical-chemical changes were manifested by changes in the Atterberg limits and pH of the treated material. A linear increase in Atterberg limits with increases in pH was noted. Soil hardening occurred at a rate of about 1/2 in. per day throughout most of the soil specimen and was found to be directly related to the changes in pH and Atterberg limits.