Upper-Bound Limit Analysis of Unsaturated Soil Slopes under Rainfall
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 144, Issue 9
Abstract
This paper presents an analytical framework for the stability analysis of unsaturated soil slopes under rainfall. The conventional log-spiral upper bound limit analysis for dry and saturated soil slopes is extended to unsaturated soil slopes by incorporating matric suction and rainfall infiltration. For an unsaturated soil slope under rainfall, shallow translational failure may be more critical than rotational failure. Hence, a translational failure mechanism in the context of upper bound plasticity theory is proposed, and its effectiveness is validated by finite-element analysis. Through the dimensionless stability charts developed by the upper bound limit analysis, the controlling factors on the failure mode of unsaturated soil slopes under rainfall are identified and investigated.
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Acknowledgments
The first author gratefully acknowledges the research scholarship (2013–2017) provided by Nanyang Technological University, Singapore. In addition, the authors would like to thank the editor and the anonymous reviewers for their constructive comments which considerably improved the manuscript.
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Journal of Geotechnical and Geoenvironmental Engineering
Volume 144 • Issue 9 • September 2018
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©2018 American Society of Civil Engineers.
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Received: May 10, 2017
Accepted: Apr 13, 2018
Published online: Jul 9, 2018
Published in print: Sep 1, 2018
Discussion open until: Dec 9, 2018
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