Reliability Analysis of Unsaturated Soil Slopes
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 131, Issue 11
Abstract
Many soil slopes are unsaturated in their initial state, and suction contributes to initial stability. Stability of these slopes decreases as suction decreases with time due to rainfall infiltration and water redistribution. Many of the parameters in the assessment of stability are highly variable. In this technical note, sensitivity/reliability analysis of design variables for a typical unsaturated soil slope is conducted. Sensitivity analysis shows that suction parameters have significant influence on the stability. Reliability computations performed for the slope considered show that failure zones are better captured by the reliability index than the conventional factor of safety. The study also shows that variation of saturated hydraulic conductivity significantly influences slope reliability.
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Acknowledgments
The results presented in this paper are part of the research project “Risk assessment in landslides,” sponsored by the Council of Scientific and Industrial Research, New Delhi. Its financial assistance is gratefully acknowledged. The writers thank Mr. M. D. Mukesh for his help in the preparation of the paper. They also thank the anonymous reviewers for their critical comments and suggestions.
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Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 131 • Issue 11 • November 2005
Pages: 1423 - 1428
Copyright
© 2005 ASCE.
History
Received: Sep 26, 2002
Accepted: Mar 18, 2005
Published online: Nov 1, 2005
Published in print: Nov 2005
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