Application of Electro-osmosis to Accelerate the Removal of Water form Fine Soils

Document Type : Research Paper

Authors

1 Post graduate of water structures, Irrigation and Reclamation department, college of agricultural and natural resources, University of Tehran.

2 Assistant Prof, Irrigation and Reclamation department, college of agricultural and natural resources, University of Tehran.

3 Ph.D. candidate of water structures, Irrigation and Reclamation department, college of agricultural and natural resources, University of Tehran.

Abstract

Nowadays, application of Electro osmosis to remove water out of the soil is one of the most efficient methods of fine soil improvement. The electric field created by electrodes placed in the soil, cause water molecules move and get extracted from the porous media. In this research, an electro-osmosis system assembled as vertical drains was applied in a laboratory scale, for treatment and improvement of fine soil. For the purpose some saturated clay samples were prepared and placed in the designed physical model and tested. The results showed that using electro osmosis to withdraw water from the soil the quantity of water will be more and the extraction done more quickly. Also an increase in the difference of voltage between cathode and anode will increase the volume of water leaving the soil. Measurement of electrical conductivity (EC) and pH length wise in the soil showed that in electro osmotic process, pH will increase around the cathode and decrease at the anode. while EC being increased at either the cathode or anode. Also it was observed that the applied voltage to the soil sample decreases from anode to the cathode. Then it is concluded that the electro osmotic method can be a suitable alternative for soil settlement instead of surcharge being applied.

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References

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Iranian Journal of Soil and Water Research
Volume 45, Issue 4 - Serial Number 4
January 2015
Pages 491-497

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