Numerical Assessment of Equivalent Radius for Electrokinetic Geosynthetics Electrodes during Electroosmotic Consolidation
Publication: International Journal of Geomechanics
Volume 18, Issue 5
Abstract
Electrokinetic geosynthetics (EKG) has been used as an electrode to perform electroosmotic consolidation for the improvement of soft soil. To use previous analytical theories to analyze the drainage and consolidation behavior of soil mass, the band-shaped EKG electrodes need to be converted to cylindrical electrodes; however, no definitive principle for this conversion is available. In the present study, six commonly used equivalent equations for a prefabricated vertical drain (PVD) were proposed for the conversion of the EKG electrode, and a numerical model was developed to evaluate their validity in terms of electric current, average degree of consolidation, and surface settlement. The effects of electrode configuration and electrode dimensions are also discussed based on the numerical results. Considering the overall performance on the analysis of the electroosmotic consolidation process, the equivalent equations were recommended to convert the band-shaped electrode to a cylindrical electrode. The electrode configuration and electrode dimensions showed a significant effect on the electroosmosis process. The hexagonal electrode configuration presented larger electric current, average degree of consolidation, and settlement than the parallel and rhombic electrode configurations. With the increase in electrode width and thickness, the electric current, average degree of consolidation, and settlement increased.
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Acknowledgments
Financial support from the National Natural Science Foundation of China (Project Nos. 51579132, 51323014, and 51609123), the Ministry of Education (Project THZ-02-2-20161080101), and the China Postdoctoral Science Foundation (Grant 2015M581104) are gratefully acknowledged.
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Published In
International Journal of Geomechanics
Volume 18 • Issue 5 • May 2018
Copyright
© 2018 American Society of Civil Engineers.
History
Received: Apr 12, 2017
Accepted: Nov 14, 2017
Published online: Mar 9, 2018
Published in print: May 1, 2018
Discussion open until: Aug 9, 2018
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