One-Dimensional Consolidation of Unsaturated Soil Subjected to Time-Dependent Loading with Various Initial and Boundary Conditions
Publication: International Journal of Geomechanics
Volume 14, Issue 2
Abstract
This study assesses the one-dimensional (1D) consolidation of unsaturated soil subjected to time-dependent loading based on the 1D consolidation theories of unsaturated soil. The differential quadrature method (DQM) is used to produce a general solution that considers various boundary conditions, various initial pore-water and pore-air distributions, and complex time-dependent loading. A special case in which the analytical solution is available in the literature is used for verification and accuracy analysis. It is found that the DQM solution can deliver more accurate results compared with the finite-difference method with a small number of sampling points. The general solution can avoid cumbersome computations in solving eigenequations encountered with the analytical solution. In addition, the proposed solution is more suitable for practical engineering because of its generality in complex initial, boundary, and loading conditions. Finally, the characteristics of the 1D consolidation of unsaturated soils under various initial pore pressure distributions, boundary conditions, and complex time-dependent loading conditions are investigated, and it is found that the initial and boundary conditions have a significant influence on the consolidation of unsaturated soils.
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Acknowledgments
This work is supported by the Research Committee of the University of Macau under Research Grant Nos. MYRG189(Y2-L3)-FST11-ZWH and MYRG067(Y1-L2)-FST12-ZWH. The financial support from the Macau Science and Technology Development Fund (Grant No. FDCT/011/2013/A1) is also gratefully acknowledged.
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Published In
International Journal of Geomechanics
Volume 14 • Issue 2 • April 2014
Pages: 291 - 301
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Dec 18, 2012
Accepted: May 1, 2013
Published online: May 3, 2013
Published in print: Apr 1, 2014
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