Generalized Analytical Solution for the Consolidation of Unsaturated Soil under Partially Permeable Boundary Conditions
Publication: International Journal of Geomechanics
Volume 17, Issue 9
Abstract
Previous studies have usually idealized the boundary conditions of unsaturated soil as absolutely permeable or impermeable. However, this assumption is not sound for the majority of cases where the boundary is partially permeable. In this study, partially permeable conditions are described using exponential functions for the excess pore-air and pore-water pressures at the boundaries. A generalized analytical solution for the consolidation of unsaturated soil under these proposed boundary conditions and constant initial excess pore-air and pore-water pressure conditions were obtained. The results of the proposed solution agreed with an analytical solution available in the literature, which verifies the feasibility of this study. The proposed solutions were subsequently tested and compared to published experimental data. Furthermore, a new concept, degree of drainage, was developed to characterize the partial-drainage conditions at the boundaries. Finally, a parametric study was carried out to show the consolidation characteristics under different degrees of drainage and ratios of hydraulic conductivities of air and water phases. The excess pore-pressure dissipation processes at the boundaries and the average degrees of consolidation for both the air and water phases are presented and discussed.
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Acknowledgments
The authors gratefully acknowledge financial support from the Macau Science and Technology Development Fund (FDCT) (Code 125/2014/A3) and the University of Macau Research Fund (MYRG2014-00175-FST). The authors appreciate the comments and suggestions of the reviewers during the peer-review process.
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Published In
International Journal of Geomechanics
Volume 17 • Issue 9 • September 2017
Copyright
© 2017 American Society of Civil Engineers.
History
Received: Jul 20, 2016
Accepted: Feb 13, 2017
Published online: May 2, 2017
Published in print: Sep 1, 2017
Discussion open until: Oct 2, 2017
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