Interpretation of the Bearing Capacity of Unsaturated Fine-Grained Soil Using the Modified Effective and the Modified Total Stress Approaches
Publication: International Journal of Geomechanics
Volume 13, Issue 6
Abstract
The bearing capacity of unsaturated soils is commonly estimated using the conventional shear-strength parameters determined from drained loading conditions regardless of soil type and drainage condition. However, the use of drained shear-strength parameters to interpret the bearing capacity of unsaturated fine-grained soils is not reliable because there are uncertainties with respect to the drainage conditions of both the pore-air and pore-water pressures. In the current study, a series of model footing tests is conducted in statically compacted unsaturated fine-grained soils. The model footing test results are interpreted using the modified effective-stress and total stress approaches considering the influence of matric suction. In addition, the validity of the modified total stress approach is tested using in situ plate-load test results in unsaturated fine-grained soils. The advantages, disadvantages, and limitations of using the modified effective-stress and modified total-stress approaches for engineering practice applications are discussed in this paper.
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Published In
International Journal of Geomechanics
Volume 13 • Issue 6 • December 2013
Pages: 769 - 778
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 13, 2012
Accepted: Oct 3, 2012
Published online: Oct 4, 2012
Published in print: Dec 1, 2013
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