Undrained Shear Strength of Consolidated Soft Soils
Publication: International Journal of Geomechanics
Volume 8, Issue 2
Abstract
On the basis of critical state soil mechanics, this study derives theoretical formulas for predicting the undrained shear strength of consolidated soft soils in triaxial compression and extension. Although the modified Cam-clay model is often utilized to predict the undrained shear strength of soft clays, it is applicable mainly to isotropically consolidated soils. Because of the anisotropy under consolidation, an inclined elliptical yield surface is chosen, which is different from those methods based on the original Cam-clay model. The inclined elliptical yield surface is testified to be appropriate to the consolidated soft soil and results in a better prediction of undrained strength, especially for the triaxial extension test. It is concluded that the analytical solutions obtained in this paper are in good agreement with the available test results and back-analysis of slope failures. On the basis of the investigation of soil properties, a simple formula is proposed for calculating the mean undrained shear strength along the failure surface.
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Acknowledgments
This research is sponsored by the Chinese National Science Foundation (Grant No. NSFC50479045).
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Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 8 • Issue 2 • March 2008
Pages: 105 - 113
Copyright
© 2008 American Society of Civil Engineers.
History
Received: Apr 3, 2006
Accepted: Jul 30, 2007
Published online: Mar 1, 2008
Published in print: Mar 2008
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