Unsaturated and Transient Seepage Analysis of San Luis Dam
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 143, Issue 2
Abstract
This paper uses the San Luis Dam upstream slide to evaluate the pore-water pressures at failure and progression of the phreatic surface through the fine-grained core for drawdown stability analyses. The hydraulic conductivity and compressibility parameters of saturated and unsaturated soils are calibrated using the reservoir hydrograph and 13 piezometers in order to evaluate the pore-water pressures at failure. The analyses show unsaturated and transient seepage analyses can be used to estimate pore-water pressures during drawdown for various stability analyses and evaluate the progression of the phreatic surface through the fine-grained core. The transient results also indicate the van Genuchten parameter significantly influences unsaturated soil response during drawdown. Different meshing techniques can produce consistent moisture content profiles in two different seepage software packages, but in situ measurement of moisture content and suction pressure is recommended to develop an unsaturated and transient seepage model.
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Acknowledgments
The contents and views in this paper are those of the authors and do not necessarily reflect those of any dam or reservoir owner/operator, consultant, regulatory agency or personnel, or anyone else knowledgeable about the case study referenced. In particular, the contents of this paper/publication are the personal opinions of the author(s) and may not reflect the opinions, conclusions, policies or procedures of the U.S. Bureau of Reclamation or U.S. Army Corps of Engineers.
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 143 • Issue 2 • February 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Sep 27, 2015
Accepted: Jun 22, 2016
Published online: Aug 11, 2016
Discussion open until: Jan 11, 2017
Published in print: Feb 1, 2017
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