Abstract
The influence of gases on unsaturated soils is discussed in the paper. First, the selection of stress state variables is discussed. It is shown that gas pressure as well as generalized effective stress and modified suction are required to construct a constitutive model of an unsaturated soil. The deformation mechanisms of solid, liquid and gas phases in soils are then investigated. It is realized that the deformation of gas phase interacts with the deformations of the other two phases in soils. Gas laws are used to describe the gas behavior. Similar to the other two phases in soil, the change of gas volume can be divided into an elastic part and a plastic part, and the latter part is then introduced to the soil hardening equation to reflect the impact of the gas on the soil. Then, a simple elasto-plastic model considering the gas effect for isotropic states is developed. Finally, the model predictions are given and compared with existing experimental data. A good agreement between them is found. Comparisons of the predictions between our model and Wheeler’s model are also performed.
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References
Bao C G, Zhan L T. Relationship between unsaturated soil behavior and engineering problems. Chinese J Geotech Engin, 2006, 28: 129–136
Schrefler B A. Mechanics and thermodynamics of saturated/unsaturated porous materials and quantitative solutions. Appl Mech Rev, 2002, 55: 351–388
Laloui L, Klubertanz G, Vulliet L. Solid-liquid-air coupling in multiphase porous media. Int J Numer Anal Meth Geomech, 2003, 27: 183–206
Li X S. Thermodynamics-based constitutive framework for unsaturated soils. 1: Theory. Géotechnique, 2007, 57: 411–422
Zhao C G, Liu Y, Gao F P. Work and energy equations and the principle of generalized effective stress for unsaturated soils. Int J Numer Anal Meth Geomech, 2010, doi: 10.1002/nag.839
Zhao C G, Zhang X D. Derivation of the work expression and discussion on the effective principle and the phase separation theorem in unsaturated soils. Sci China Ser E: Technol Sci, 2008, 51: 1530–1541
Zhao C G, Liu Y. Continuum porous medium soil mechanics and its application in constitutive relationship of unsaturated soils. Chin J Geotech Engin, 2009, 31: 1324–1335
Sun J C, Wang G Q, Sun Q C. Crack spacing of unsaturated soils in the critical state. Chinese Sci Bull, 2009, 54: 2008–2012
Wroth C P, Houlsby G T. Soil mechanics: Property characterization and analysis procedures. In: Proc 11th Int. Conf. Soil Mech. Found Eng, San Francisco. 1985. 1–55
Loret B, Khalili N. A three-phase model for unsaturated soils. Int J Numer Anal Meth Geomech, 2000, 24: 893–927
Houlsby G T. The work input to an unsaturated granular material. Géotechnique, 1997, 47: 193–196
Fredlund D G, Morgenstern N R. Soil Mechanics for Unsaturated Soils. Beijing: China Architecture and Building Press, 1997
Alonso E E, Gens A, Josa A. A constitutive model for partially saturated soils. Géotechnique, 1990, 40: 405–430
Tarantino A, Mongiovì L. Experimental investigations on the stress variables governing unsaturated soil behaviour at medium to high degrees of saturation. In: Tarantino A, Mancuso C, eds. Proceedings of an international workshop on unsaturated soils, Trento, Italy. Balkema, 2000. 1–20
Zhang X, Lytton R L. Stress state variables for saturated and unsaturated soils. In: Proceedings of the 4th international conference on unsaturated soils, Carefree, USA. ASCE, 2006. 2380–2391
Jommi C. Remarks on the constitutive modelling of unsaturated soils. In: Tarantino A, Mancuso C, eds. Proceedings of an international workshop on unsaturated soils, Trento, Italy. Balkema, 2000. 139–154
Vaunat J, Romero E, Jommi C. An elastoplastic hydro-mechanical model for unsaturated soils. In: Tarantino A, Mancuso C, eds. In: Proceedings of an international workshop on unsaturated soils, Trento, Italy. Balkema, 2000. 121–138
Wheeler S J, Sharma R S, Buisson M S. Coupling of hydraulic hysteresis and stress-strain behaviour in unsaturated soils. Géotechnique, 2003, 53: 41–54
Sheng D, Sloan S W, Gens A. A constitutive model for unsaturated soils: Thermomechanical and computational aspects. Comput Mech, 2004, 33: 453–465
Wei C F, Dewoolkar M M. Formulation of capillary hysteresis with internal state variables. Water Res Res, 2006, 42: W07405
Sheng D, Sloan S W, Gens A. A constitutive model for unsaturated soils: Thermomechanical and computational aspects. Comput Mech, 2004, 33: 453–465
Sun D, Sheng D, Xiang L, et al. Elastoplastic prediction of hydromechanical behaviour of unsaturated soils under undrained conditions. Comput Geotech, 2008, 35: 845–852
Raveendiraraj A. Coupling of mechanical behaviour and water retention behaviour in unsaturated soils. Dissertation for the Doctoral Degree. Glasgow: University of Glasgow, 2009
Sivakumar V, Wheeler S J. Influence of compaction procedure on the mechanical behaviour of an unsaturated compacted clay part 1: Wetting and isotropic compression. Géotechnique, 2000, 50: 359–368
Li X S. Thermodynamics-based constitutive framework for unsaturated soils 2: A basic triaxial model. Géotechnique, 2007, 57: 423–435
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Liu, Y., Zhao, C., Cai, G. et al. Constitutive modeling for unsaturated soils considering gas hardening effect. Chin. Sci. Bull. 56, 1739–1745 (2011). https://doi.org/10.1007/s11434-010-4109-0
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DOI: https://doi.org/10.1007/s11434-010-4109-0