Analytical Study of the Permeability of a Foam-Conditioned Soil

It is important to control the permeability of a mixture of foam and solid in many fields such as civil engineering, petroleum engineering, and material processing. An analytical model to estimate the coefficient of permeability of a foam-conditioned soil was developed in this study, based on the permeation theory of pure foam. In the model, water flow in the permeation channel enclosed by foam bubbles was derived using the Kozeny-Carman equation, where the reduction in the number of effective permeation channels due to the contact angle between foam bubbles and soil particles was considered. To validate the analytical model, a series of large-scale permeability tests were carried out on 18 foam-conditioned soils with various gradations and conditioning parameters, and the results were compared with the calculated coefficients of permeability. Although the calculated values underestimated the experimental values for some cases, they were in general good agreement. The validated analytical model indicated that, for fully conditioned soils, the permeability increased with an increase in the porosity of the conditioned soil and the effective particle sizes of the foam and soil.