Finite-Element Simulation for Contribution of Matric Suction and Friction Angle to Stress Distribution during Pulling-Out Process
Publication: International Journal of Geomechanics
Volume 13, Issue 5
Abstract
In slope engineering, soils are ordinarily in an unsaturated state. Today the application of unsaturated soil mechanics theory to slope stability analysis has become an essential point in geotechnical engineering research. To explain the relationship between matric suction and soil structure with slope stability (via the pulling-out effect), reasonable finite-element (FE) modules can be created. By using FE analysis (which includes the existing soil parameters), the stability of residual soil slope can be simulated under different water contents (via changes in matric suction) and soil structures (via different values). Inferring from the soil-water characteristic curve obtained from previous work, the influence of matric suction on unsaturated soil slope is determined. The importance of matric suction and soil structure is discovered during the root pulling-out analysis. The results show that because of increasing matric suction in unsaturated soil (which is the result of the decreasing degree of saturation), the required force during the pulling-out process (root anchorage) and consequently stress-distribution capacity will be increased, and the safety factor of the soil slope is amended. However, changes in soil friction angle do not affect root anchorage in roots with a sharp deviation angle (53°); for a root with a steep deviation angle (15°), as the soil structure improves by means of increases in the internal friction angle, the forces needed to determine the pull out angle, and accordingly, the stress-distribution capacity, are modified, and the safety factor is improved.
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Acknowledgments
The authors are grateful to the University of Malaya and the Ministry of Science, Technology, and Innovation and to Professor N. Shokrpour from Shiraz University of Medical Sciences, Iran, for editing the English manuscript.
References
ABAQUS [Computer software]. Palo Alto, CA, Abaqus, Inc.
ASTM. (2007). “Standard method for tension testing of Nickel-Titanium super elastic material.” F2516, West Conshohocken, PA.
Barbour, S. L., and Yanful, E. K. (1994). “A colume study of static nonequilibeium fluid pressure in sand during prolonged drainage.” Can. Geotech. J., 31(2), 299–303.
Bowles, J. E. (1996). Foundation analysis and design, 5th Ed., McGraw Hill, New York.
Choo, L. P., and Yanful, E. K. (2000). “Water flow through cover soils using modeling and experimental methods.” J. Geotech. Geoenviron. Eng., 126(4), 324–334.
Coduto, D. P. (1998). Geotechnical engineering:Principles and practices, Prentice Hall, Englewood Cliffs, NJ.
Fredlund, D. G., and Hardy, R. M. (2000). “The 1999 R. M. Hardy Lecture: The implementation of unsaturated soil mechanics into geotechnical engineering.” Can. Geotech. J., 37(5), 963–986.
Fredlund, D. G., and Morgenstern, N. R. (1978). “Stress state variables for unsaturated soils.” J. Geotech. Engrg. Div., 103(5), 447–466.
Gasmo, J. M., Tahardjo, H., and Leong, E. C. (2000). “Infiltration effects on stability of a residual soil slope.” Comput. Geotech., 26(2), 145–165.
Hossain, K. (2010). “Effect of rainfall on matric suction and stability of a residual granite soil slope.” DUET J., 1, 37–41.
Kisch, M. (1959). “The theory of seepage from clay-blanketed reservoirs.” Geotechnique, 9(1), 9–21.
Sweeney, D. J. (1982). “Some in situ soil suction measurements in Hong Kong’s residual soil slopes.” Proc., 7th Southeast Asia Geotechnical Conf., Vol. 1, Hong Kong, 91–106.
Terzaghi, K. (1943). Theoretical Soil Mechanics, Wiley, New York.
Tsaparas, I., Rahardjo, H., Toll, D. G., and Leong, E. C. (2002). “Controlling parameters for rainfall-induced landslide.” Comput. Geotech., 29(1), 1–27.
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© 2013 American Society of Civil Engineers.
History
Received: Sep 16, 2011
Accepted: Jul 24, 2012
Published online: Aug 9, 2012
Published in print: Oct 1, 2013
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