Strength and Stiffness Properties of an Unsaturated Clayey Silt: Experimental Study at High Degrees of Saturation
Publication: International Journal of Geomechanics
Volume 21, Issue 7
Abstract
Unsaturated constant water content triaxial compression tests with suction measurement, using an Imperial College tensiometer, and saturated consolidated undrained tests were conducted on reconstituted brickearth, a naturally unsaturated clayey silt from London. The results show that the saturated effective stress can be applied to the critical state line (CSL) and normalized stiffness for unsaturated brickearth but that Bishop's effective stress variable gives a slightly improved CSL. The stiffness derived from local instrumentation demonstrates that Bishop's effective stress is also beneficial for normalizing the stiffness modulus over the small-strain range (up to axial strains of about 3%).
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Acknowledgments
The authors are grateful to the Engineering and Physical Sciences Research Council (EPSRC) who funded the first author through a Doctoral Prize Fellowship. They also thank Mssrs. Steve Ackerley, Graham Keefe, and Duncan Parker for their technical support and Dr Tingfa Liu for help with the experiments. The authors thank the anonymous reviewers whose helpful comments on the original submission significantly strengthened this paper.
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Published In
International Journal of Geomechanics
Volume 21 • Issue 7 • July 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Nov 22, 2019
Accepted: Jan 26, 2021
Published online: Apr 21, 2021
Published in print: Jul 1, 2021
Discussion open until: Sep 21, 2021
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Cited by
- Xiuhan Yang, Sai K. Vanapalli, Mechanisms and Modeling Methods of Strain-Softening Behavior of Unsaturated Soils, International Journal of Geomechanics, 10.1061/IJGNAI.GMENG-7934, 23, 5, (2023).