Constitutive Model for Drained Compression of Unsaturated Clay to High Stresses
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 143, Issue 6
Abstract
A constitutive model is presented in this paper to describe the isotropic compression response of unsaturated, compacted clay under drained conditions over a wide range of mean effective stresses. The model captures the key transition points of the compression curves at different stress levels, ranging from the preconsolidation stress, to pressurized saturation, to the initiation of void closure. The results from drained, isotropic compression tests on compacted clay specimens having different initial degrees of saturation up to a mean total stress of 160 MPa were used for model calibration. The suction hardening effect on the preconsolidation stress and the nonlinear compression curve of unsaturated clay up to the point of pressurized saturation were captured using an extended form of an existing effective stress-based constitutive model. For higher mean stresses, an empirical relationship to consider the transition to void closure was incorporated to fit the observed compression curves of the compacted clay specimens. The transition to void closure was found to be affected by the initial compaction conditions despite the fact that all of the specimens were pressure saturated in this mean stress range.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
Funding for this research was provided by Office of Naval Research (ONR) Grant No. N00014-11-1-0691. The opinions in this paper are those of the authors alone.
References
Akers, S. A. (2001). “Two-dimensional finite element analysis of porous geomaterials at multikilobar stress levels.” Ph.D. thesis, Dept. of Civil Engineering, Virginia Polytechnic Institute and State Univ., Blacksburg, VA.
Akers, S. A., Adley, M. D., and Cargile, J. D. (1995). “Comparison of constitutive models for geologic materials used in penetration and ground shock calculations.” Proc., 7th Int. Symp. on Interaction of the Effects of Munitions with Structures, Mannheim, Germany.
Alonso, E. E., Gens, A., and Josa, A. (1990). “A constitutive model for partly saturated soils.” Géotechnique, 40(3), 405–430.
Bishop, A. W. (1959). “The principle of effective stress.” Teknisk Ukeblad I Samarbeide Med Teknikk, 106(39), 859–863.
Bolzon, G., and Schrefler, B. A. (1995). “State surfaces of partially saturated soils: An effective pressure approach.” Appl. Mech. Rev., 48(10), 643–649.
Bolzon, G., Schrefler, B. A., and Zienkiewicz, O. C. (1996). “Elastoplastic soil constitutive laws generalised to partially saturated states.” Géotechnique. 46(2), 279–289.
Cui, Y. J., Delage, P., and Sultan, N. (1995). “An elastoplastic model for compacted soils.” Proc., 1st Int. Conf. on Unsaturated Soils, E. E. Alonzo and P. Delage, eds., A. A. Balkema, Rotterdam, Netherlands, 703–709.
Fox, P. J., and Pu, H. F. (2012). “Enhanced CS2 model for large strain consolidation.” Int. J. Geomech., 574–583.
Gallipoli, G., Gens, A., Sharma, R., and Vaunat, J. (2003). “An elasto-plastic model for unsaturated soil incorporating the effects of suction and degree of saturation on mechanical behaviour.” Géotechnique, 53(1), 123–135.
Georgiadis, K., Potts, D. M., and Zdravkovic, L. (2005). “Three-dimensional constitutive model for partially and fully saturated soils.” Int. J. Geomech., 244–255.
Hilf, J. W. (1948). “Estimating construction pore pressures in rolled earth dams.” Proc., 2nd Int. Conf. on Soil Mechanics and Foundation Engineering, Vol. 3, A. A. Balkema, Rotterdam, Netherlands, 230–240.
Josa, A., Balmaceda, A., Gens, A., and Alonso, E. E. (1992). “An elastoplastic model for partially saturated soils exhibiting a maximum of collapse.” Proc., 3rd Int. Conf. on Computational Plasticity, Barcelona, Spain, 815–826.
Jotisankasa, A., Ridley, A., and Coop, A. (2007). “Collapse behavior of a compacted silty clay in the suction-monitored oedometer apparatus.” J. Geotech. Geoenviron. Eng., 867–877.
Khalili, N., Geiser, F., and Blight, G. E. (2004). “Effective stress in unsaturated soils: A review with new evidence.” Int. J. Geomech., 4(2), 115–126.
Khalili, N., Habte, M. A., and Zargarbashi, S. (2008). “A fully coupled flow deformation model for cyclic analysis of unsaturated soils including hydraulic and mechanical hystereses.” Comput. Geotech., 35(6), 872–889.
Kohgo, Y., Nakano, M., and Miyazaki, T. (1993). “Theoretical aspects of constitutive modelling for unsaturated soils.” Soils Found., 33(4), 49–63.
Lloret, A., Villar, M. V., Sanchez, M., Gens, A., Pintado, X., and Alonso, E. E. (2003). “Mechanical behaviour of heavily compacted bentonite under high suction changes.” Géotechnique, 53(1), 27–40.
Loret, B., and Khalili, N. (2002). “An effective stress elastic-plastic model for unsaturated porous media.” Mech. Mater., 34(2), 97–116.
Mitchell, J. K., Hooper, D. R., and Campanella, R. G. (1965). “Permeability of compacted clay.” J. Soil Mech. Found. Div., 91(SM4), 41–65.
Mun, W., and McCartney, J. S. (2015). “Compression mechanisms of unsaturated clay under high stress levels.” Can. Geotech. J., 52(12), 2099–2112.
Mun, W., and McCartney, J. S. (2016). “Constitutive model for the undrained compression of unsaturated clay.” J. Geotech. Geoenviron. Eng., .
Sheng, D., Fredlund, D. G., and Gens, A. (2008). “A new modelling approach for unsaturated soils using independent stress variables.” Can. Geotech. J., 45(4), 511–534.
Sivakumar, V. (1993). “A critical state framework for unsaturated soils.” Ph.D. thesis, Univ. of Sheffield, Sheffield, U.K.
Sun, D. A., Sun, W. J., and Xiang, L. (2010). “Effect of degree of saturation on mechanical behaviour of unsaturated soils and its elastoplastic simulation.” Comput. Geotech., 37(5), 678–688.
Tarantino, A. (2007). “A possible critical state framework for unsaturated compacted soils.” Géotechnique, 57(4), 385–389.
Uchaipichat, A., and Khalili, N. (2009). “Experimental investigation of thermo-hydro-mechanical behaviour of an unsaturated silt.” Géotechnique, 59(4), 339–353.
van Genuchten, M. T. (1980). “A closed-form equation for predicting the hydraulic conductivity of unsaturated soils.” Soil Sci. Soc. Am. J., 44(5), 892–898.
Wayllace, A., and Lu, N. (2012). “A transient water release and imbibitions method for rapidly measuring wetting and drying soil water retention and hydraulic conductivity functions.” Geotech. Test. J., 35(1), 103–117.
Wheeler, S. J., Gallipoli, D., and Karstunen, M. (2002). “Comments on the use of Barcelona basic model for unsaturated soils.” Int. J. Numer. Anal. Methods Geomech., 26(15), 1561–1571.
Wheeler, S. J., Sharma, R. S., and Buisson, M. S. R. (2003). “Coupling of hydraulic hysteresis and stress-strain behaviour in unsaturated soils.” Géotechnique, 53(1), 41–54.
Wheeler, S. J., and Sivakumar, V. (1995). “An elastoplastic critical state framework for unsaturated soil.” Géotechnique, 45(1), 35–53.
Zhou, A. N., Sheng, D., Scott, S. W., and Gens, A. (2012a). “Interpretation of unsaturated soil behaviour in the stress-saturation space. I: Volume change and water retention behaviour.” Comput. Geotech., 43, 178–187.
Zhou, A. N., Sheng, D., Scott, S. W., and Gens, A. (2012b). “Interpretation of unsaturated soil behaviour in the stress-saturation space. II: Constitutive relationships and validations.” Comput. Geotech., 43, 111–123.
Zimmerman, H. D., Wagner, M. H., Carney, J. A., and Ito, Y. M. (1987). “Effects of site geology on ground shock environments.”, U.S. Army Corps of Engineers, Vicksburg, MS.
Information & Authors
Information
Published In
Copyright
©2017 American Society of Civil Engineers.
History
Received: Nov 26, 2015
Accepted: Oct 12, 2016
Published online: Feb 15, 2017
Published in print: Jun 1, 2017
Discussion open until: Jul 15, 2017
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.