Equivalent Stress Equation for Unsaturated Soils. II: Solid-Porous Model
This article is a reply.
VIEW THE ORIGINAL ARTICLEThis article has a reply.
VIEW THE REPLYPublication: International Journal of Geomechanics
Volume 8, Issue 5
Abstract
Based on the study of the equilibrium of the particles of a soil showing a bimodal structure and subject to certain suction, it was possible to establish an analytical expression for the value of Bishop’s parameter (see the companion paper). This parameter can be written as a function of the saturated fraction and the degree of saturation of the unsaturated fraction of the soil. However, the determination of these last two parameters cannot be made from current experimental procedures. Therefore, a solid-porous model simulating the structure of the soil is proposed herein and used to determine these parameters. The data required for the solid-porous model are obtained from the grain and pore size distributions, void ratios, and secondary soil–water retention curves of the soil. The plots of the deviator stress versus equivalent stress shows a unique failure line for a series of tests performed at different confining net stresses and suctions, confirming that the proposed equivalent stress equation is adequate to predict the shear strength of unsaturated soils. It also results in different strengths for wetting and drying, as the experimental evidence suggests.
Get full access to this article
View all available purchase options and get full access to this article.
References
Collins, K., and McGown, A. (1974). “The form and function of microfabric features in a variety of natural soils.” Geotechnique, 24(2), 223–254.
Cunningham, M. R., Ridley, A. M., Dineen, K., and Burland, J. B. (2003). “The mechanical behavior of a reconstituted unsaturated silty clay.” Geotechnique, 53(2), 183–194.
Escario, V., Jucá, J. E. T., and Coppe, M. S. (1989). “Strength and deformation of partly saturated soils.” Proc., 12th Int. Conf. on Soil Mechanics and Foundation Engineering, Rio de Janeiro, International Society for Soil Mechanics and Foundation Engineering, 43–49.
Espitia, J. (2005). “Experimental study on Speswhite kaolin.” Research Project, Univ. of Queretaro, Queretaro, Mexico.
Everett, D. H. (1967). The solid–gas interface, E. Flood, ed., Dekker, New York, 1005–1010.
Fredlund, D. G., and Xing, A. (1994). “Equations for the soil–water characteristic curve.” Can. Geotech. J., 31(3), 521–532.
Haines, W. B. (1929). “The hysteresis effect in capillary properties and the mode of moisture distribution associated therewith.” J. Agric. Sci., 20, 7.
He, M., Szuchmacher, A., Aston, D. E., Buenviaje, C., Overney, R., and Luginbuhl, R. (2001). “Critical phenomenon of water bridges in nanoasperity contacts.” J. Chem. Phys., 114(3), 1355–1360.
Mayagoita, V., and Kornhauser, I. (1993). “Description of heterogeneous surfaces in activated chemisorptions.” Fundamentals of adsorption IV, M. Suzuki, ed., Kodansha, Tokio, 421–428.
Mayagoitia, V., Rojas, F., and Kornhauser, I. (1988). “Domain complexions in capillary condensation.” J. Chem. Soc., Faraday Trans., 84, 785–799.
Morrow, N. R. (1970). Ind. Eng. Chem., 62, 32.
Penumadu, D., and Dean, J. (2000). “Compressibility effect in evaluating the pore-size distribution of kaolin clay using mercury intrusion porosimetry.” Can. Geotech. J., 37(2), 393–405.
Ray, R. P., and Morris, K. B. (1995). “Automated laboratory testing for soil-water characteristic curves.” Proc., 1st Int. Conf. on Unsaturated Soils, Elsevier, Paris, 547–552.
Rojas, E., and Rojas, F. (2005). “Modeling hysteresis of the soil-water characteristic curve.” Soils Found., 45(3), 135–146.
Romero, E., Gens, A., and Lloret, A. (1999). “Water permeability, water retention, and microstructure of unsaturated compacted Boom clay.” Eng. Geol. (Amsterdam), 54(1-2), 117–127.
Sheng, D., Sloan, D. G., and Gens, A. (2004). “A constitutive model for unsaturated soils: thermomechanical and computational aspects.” Comput. Mech., 33(6), 453–465.
Simms, P. H., and Yanful, E. K. (2001). “Measurement and estimation of pore shrinkage and pore distribution in a clayey till during soil–water characteristic curve tests.” Can. Geotech. J., 38(4), 741–754.
Simms, P. H., and Yanful, E. K. (2003). “Pore network modelling for unsaturated soils.” Proc., 56th Canadian Geotechnical Conf., Winnipeg, Canada.
Simms, P. H., and Yanful, E. K. (2004). “A discussion of the application of mercury intrusion porosimetry for the investigation of soils, including an evaluation of its use to estimate volume change in compacted clays.” Geotechnique, 54(6), 421–426.
Sivakumar, V. (1993). “A critical state framework for unsaturated soils.” Ph.D. thesis, Univ. of Sheffield, Sheffield, U.K.
Stark, U. (1993). “Using Coulter LS130 laser diffraction analysis for testing and research work on building materials.” Sond. ZGK Int., 8, 458–462.
Tamagnini, R. (2004). “An extended Cam-clay model for unsaturated soils with hydraulic hysteresis.” Geotechnique, 54(3), 223–228.
Taylor, D. W. (1954). Fundamentals of soil mechanics, Wiley, New York.
Vanapalli, S. K., Fredlund, D. E., Pufahl, D. E., and Clifton, A. W. (1996). “Model for the prediction of shear strength with respect to soil suction.” Can. Geotech. J., 33(3), 379–392.
Wheeler, S., and Sivakumar, V. (1995). “An elastoplastic critical state framework for unsaturated soils.” Geotechnique, 45(1), 35–53.
Wheeler, S. J., Sharma, R. S., and Buisson, M. S. R. (2003). “Coupling hydraulic hysteresis and stress–strain behavior in unsaturated soils.” Geotechnique, 53(1), 41–54.
Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 8 • Issue 5 • September 2008
Pages: 291 - 299
Copyright
© 2008 ASCE.
History
Received: Oct 9, 2006
Accepted: Mar 7, 2008
Published online: Sep 1, 2008
Published in print: Sep 2008
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.