Fractal model for water–mineral interaction of expansive soils

Water–mineral interaction in expansive soils is discussed under environmental loads in water chemistry. Water and clay particles interact with each, and water molecules are strongly attracted to and adsorbed on clay particle surfaces of expansive soils. The normalized adsorbed water volume to the montmorillonite volume of expansive soils is deduced from the energy balance based on the surface fractal model for montmorillonite. A postulate of mass transfer of adsorbed water from solid-to-solution fraction caused by chemical load is then discussed. Theory on effective stress of expansive soils affected by chemical loads is developed to deal with the effects of chemical swell and shear strength. The generalized theories on the swelling deformation and shear strength of expansive soils are developed to deal with the effects of chemical loads.