Analytical Investigation of Electroosmotic Consolidation in Unsaturated Soils Considering the Coupling Effect and a Nonuniform Initial Water Content
Publication: International Journal of Geomechanics
Volume 21, Issue 8
Abstract
Electroosmosis often dewaters soil into unsaturated conditions. Due to the shrinkage deformation and decrease of effective voltage that occur during the electroosmotic consolidation as the soil changes from the saturated to unsaturated state, an analytical solution with the consideration of the coupled deformation and time-decreasing effective voltage was developed for one-dimensional (1D) electroosmotic consolidation in unsaturated soils. The effect of nonuniform distribution of the initial water content was also considered. To validate the effectiveness of the proposed analytical solution, a laboratory test was conducted. Thereafter, the proposed solution was used in a parametric study to investigate the effects of the coupled deformation, distribution pattern of the initial water content, and decrease rate of the effective voltage. The results indicated that the coupling effect increases with a decrease in the desaturation coefficient, and the coupling effect is significant for soft soils with high retention capability and compressibility. The nonuniform distribution of initial water content also had a great influence on the consolidation rate. When the initial water content increased from the anode to the cathode, the consolidation rate was fast in that direction but slow in the other direction. Finally, with the consideration of time-decreasing effective voltage, the calculated maximum matric suction and drainage decreased and the completion time of electroosmotic consolidation was shortened. In summary, the analytical solution developed in this study could capture the actual problems for electroosmosis consolidation in field applications to some extent.
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Acknowledgments
The authors greatly appreciate the financial support from the Fundamental Research Funds for the Central Universities (2019B11214) and the National Natural Science Foundation of China (U1765205 and 51509077). The first author is grateful for the financial support from the China Scholarship Council (CSC) (201806715020) for his joint research at UPC, Barcelona Tech. Finally, we greatly thank the reviewers and the editor for their professional comments to improve the quality of this paper.
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International Journal of Geomechanics
Volume 21 • Issue 8 • August 2021
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© 2021 American Society of Civil Engineers.
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Received: Aug 24, 2019
Accepted: Feb 3, 2021
Published online: May 21, 2021
Published in print: Aug 1, 2021
Discussion open until: Oct 21, 2021
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