Predicting Shear Strength of Unsaturated Soils over Wide Suction Range
Publication: International Journal of Geomechanics
Volume 20, Issue 2
Abstract
Unsaturated soils over a wide suction range are widespread in nature. The shear strength of unsaturated soils is a fundamental property in various geotechnical designs. In this paper, a systematic study was conducted to investigate the effect of soil type on the shear strength of unsaturated soils. Shear strength for different types of soil over a wide suction range can be roughly classified into three types. Numerous existing shear-strength equations of unsaturated soils were used to predict the shear strength of different types of soil over a wide suction range, and the advantages and limitations of those equations were discussed. In addition, new equations for the shear strength of unsaturated soils were proposed based on the relationship between the average skeleton stress and the suction over a wide suction range. The results showed good agreement between the predicted and measured shear strengths results over a wide suction range for sand and silty soils.
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Acknowledgments
The authors express their gratitude for the grants provided by the National Natural Science Foundation of China (Nos. 41902279, 11672172, and 41630633). The first author was sponsored by the K. C. Wong Magna Fund at Ningbo University and the China Scholarship Council (No. 201706890064) during this study.
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Published In
International Journal of Geomechanics
Volume 20 • Issue 2 • February 2020
Copyright
©2019 American Society of Civil Engineers.
History
Received: Aug 29, 2018
Accepted: Jun 12, 2019
Published online: Dec 12, 2019
Published in print: Feb 1, 2020
Discussion open until: May 12, 2020
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