Skip to main content
Log in

Micromechanics analysis for unsaturated granular soils

Acta Mechanica Solida Sinica Aims and scope Submit manuscript

Abstract

This paper aims at establishing an anisotropic stress expression for unsaturated pendular-state granular soils. Using the second-order fabric tensor, we formulate a micromechanics scheme of soils with statistically averaging method, and reveal that the macroscopic average stress of unsaturated granular soils in pendular-state is not isotropic. Not only is the stress from contact forces anisotropic due to the fabric, but also the capillary stress is directional dependent, which is different from the common point that the capillary stress is isotropic. The capillary stress of unsaturated pendular-state granular soils is determined by the orientation distribution of contact normals, so it is closely related to the initial and induced anisotropy of soils. Finally, DEM numerical simulations of triaxial compression tests of pendular-state soils at different degrees of saturation are used to verify the existence of above anisotropy of stresses.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Dantu, P., Contribution à 1’étude mechanique et geometrique des milieux epulverulents. In: Proceedings of the Fourth International Conference Soil Mech, 1957, 1: 144–148.

    Google Scholar 

  2. Weber, J., Recherche concernant les contraintes intergranulaires dans les milieux pulvérulents. Bulletin de Liaison des Ponts et Chaussees, Paris, 1966, 20: 1–20.

    Google Scholar 

  3. Christoffersen, J., Mehrabadi, M.M. and Nemat-Nasse, S., A micromechanical description on granular material behavior. Journal of Applieded Mechanics, 1981, 48: 339–344.

    Article  Google Scholar 

  4. Mehrabadi, M.M., Nemat-Nasser, S. and Oda, M., On statistical description of stress and fabric in granular materials. International Journal of Numerical and Analytical Method in Geomechanic, 1982, 6: 95–108.

    Article  MathSciNet  Google Scholar 

  5. Cundall, P.A. and Strack, O.D.L., Modeling of microscopic mechanisms in granular materials. In: Jenkins, J.T., Satake, M. (Eds.). Proceedings of the US-Japan seminar on new models and constitutive relations in the mechanics of granular materials, 1983: 137–149.

    Chapter  Google Scholar 

  6. Thornton, C. and Barnes, D.J., Computer simulated deformation of compact granular assemblies. Acta Mechanica, 1986, 64: 45–61.

    Article  Google Scholar 

  7. Bathurst, R.J. and Rothenberg, L., Micromechanical aspects of isotropic granular assemblies with linear contact interactions. ASME Journal of Applied Mechanics, 1988, 55: 17–23.

    Article  Google Scholar 

  8. Mehrabadi, M.M. and Loret, B., Incremental constitutive relations for granular materials based on micromechanics. Proceedings of the Royal Society of London, 1993, 441: 443–463.

    MATH  Google Scholar 

  9. Chang, C.S. and Hicher, P.Y., An elastoplastic model for granular materials with microstructural consideration. International Journal of Solid and Structures, 2005, 42(14): 4258–4277.

    Article  Google Scholar 

  10. Terzaghi, K., Principles of Soil Mechanics. New York: John Wiley and Sons, 1963.

    Google Scholar 

  11. Bear, J., Dynamics of Fluids in Porous Media, New York: Elsevier, 1972.

    MATH  Google Scholar 

  12. Bishop, A.W and Blight, G.E., Some aspects of effective stress of in saturated and partially saturated soils. Géotechnique, 1963, 13: 177–179.

    Article  Google Scholar 

  13. Li, X.S., Effective stress in unsaturated soil: A microstructural analysis. Géotechnique, 2003, 53: 273–277.

    Article  Google Scholar 

  14. Molenkamp, F. and Nazemi, A.H., Micromechanical considerations of unsaturated pyramidal packing. Géotechnique, 2003, 53(2): 195–206.

    Article  Google Scholar 

  15. James, K. Mitchell and Kenichi, Fundamentals of Soil Behavior. Hoboken, New Jersey: John Wiley & Sons, Inc., 2004.

    Google Scholar 

  16. Fisher, R.A., On the capillary forces in an ideal soil; Corrections of formulae given by Haines, W.B. Journal of Agricultural Science, 1926, 16: 492–505.

    Article  Google Scholar 

  17. Lu, N., Wu, B. and Tan, C.P., Tensile strength characteristics of unsaturated sands. Journal of Geotechnical and Geoenviromental Engineering, ASCE, 133: 144–154. doi:10.1061/(ASCE) 1090–0241, 2007, 133: 2(144).

  18. Lian, G., Thornton, C. and Adams, M.J., A Theoretical study of liquid bridge force between rigid spherical bodies. Journal of Collide and Interface Science, 1993, 161: 138–147.

    Article  Google Scholar 

  19. Pietsch, W.B., Tensile strength of granular materials. Nature, 1968, 217: 736–737.

    Article  Google Scholar 

  20. Gili, Y.Y., Modelo microstructural para medios hranulares ni saturados. Doctoral Thesis, Universitat Politècnica de Catalunya, 1988.

  21. Hill, R., The essential structure of constitutive laws for metal composite sand polycrystals. Journal of the Mechanics and Physics of Solids, 1967, 15: 79–95.

    Article  Google Scholar 

  22. Gray, W.A., The Packing of Solid Particles. London: Chapman and Hall, 1968.

    Google Scholar 

  23. Oda, M., Nemat-Nasser, S. and Meharabadi, M.M., A statistical study of fabric in random assembly of spherical granulates. International Journal of Numerical and Analytical Method in Geomechanic, 1982, 6(1): 77–94.

    Article  Google Scholar 

  24. Satake, M., Fabric tensor in granular materials. In: proc. IUTAM Symp. On Deformation and Failure of Granular materials (Edited by P.A Vermeer and H.J Luger), 1982, 63–68. Balkema, A.A., Delft, The Netherlands.

    Google Scholar 

  25. Cowin, S.C., The relationship between the elastic tensor and the fabric tensor. Mechanics of Materials, 1985, 4(2): 137–147.

    Article  Google Scholar 

  26. Rothenberg, L. and Bathurst, R.J., Analytical study of induced anisotropy in idealized granular materials. Géotechnique, 1989, 39(4), 601–614.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Weihua Zhang.

Additional information

Project supported by the National Natural Science Foundation of China (No. 50778013) and the National Basic Research Program (973) of China (No. 2010CB732100).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Zhang, W., Zhao, C. Micromechanics analysis for unsaturated granular soils. Acta Mech. Solida Sin. 24, 273–281 (2011). https://doi.org/10.1016/S0894-9166(11)60028-1

Download citation

  • Received:

  • Revised:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1016/S0894-9166(11)60028-1

Key words

Navigation