ABSTRACT
Despite the aforementioned advances to describe the stress partitioning mechanisms in unsaturated soils there is a need to properly extend the thermodynamics to swelling clays, highly sensible to salinity changes (or more general ion concentration) and disjoining pressure. In spite of the well accepted incorporation of the chemical expansion stress in the effective stress principle strongly dependent on ion concentration, the multi-scale derivation of this quantity based on the nanopore modeling seated on Poisson-Boltzmann theory was accomplished in fully saturated clays (Murad and Moyne 2002, 2008). The extension to clayey soils with two levels of porosity (nano-and micropores) with the latter partially saturated with water and air is still an open issue.
