A Constitutive Model for Unsaturated Soils Using Degree of Capillary Saturation and Effective Interparticle Stress as Constitutive Variables

  • Annan ZhouEmail author
  • Shengshen Wu
  • Jie Li
Conference paper


This paper discusses the role of the degree of capillary saturation in modelling the coupled hydro-mechanical behaviour of unsaturated soils and proposes a new constitutive model for unsaturated soils by using the degree of capillary saturation and the effective inter-particle stress. In the model, the shear strength, yield stress and deformation behaviour of unsaturated soils are governed directly by the above two constitutive variables. The model is then validated against a variety of experimental data in the literature, and the results show that a reasonable agreement can be obtained using this new constitutive model.


Unsaturated soil Degree of capillary saturation Constitutive model 


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© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Royal Melbourne Institute of Technology (RMIT)MelbourneAustralia

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