Using considerably lower moisture clay bed than that used in previous studies, experimental studies have been carried out under constant electric current. The clay bed used had initially plasticity and its initial moisture content was about 0.32 kg/kg-solid. It was found that water in such a low moisture clay bed could be easily removed by eleclroosmosis and its moisture content could reach about 0.2 kg/kg-solid where the clay bed became firm and hard. The moisture changes in the clay bed were investigated analytically by assuming that the driving forces of moisture migration in the bed were the electroosmotic action and the gradient of osmotic suction pressure. It was recognized that the experimental results of changes of moisture content distribution agreed with the analytical results. It was also found that after a long time a final moisture distribution was formed in the clay bed where the electric current flowed but the electroosmotic flow did not occur. After reaching the final moisture distribution, it could be considered that the electroosmotic flow and the flow due to gradient of the osmotic suction pressure compensated each other.
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