Crystallization deformation of a saline soil during freezing and thawing processes

Water, salt and heat transfer in porous media generally accompanied with phase change, causing serious damages to the porous material. In this paper, a kinetics model considering nucleation, molecular diffusion and crystal growth was established. Then, a simple expression of macroscopic crystallization stress (MCS), depending on the microscopic crystallization pressure and the amount of precipitated crystal, was presented. Finally, the model was calibrated through experimental study on the deformation behavior of soil combined with phase change during freezing. The experimental results indicate that the soil deformation is determined by MCS in essentially. The MCS destroys the pore structure resulting in soil deformation when the MCS exceeds the tensile strength of the soil material. A good agreement between the model predictions and the experimental results demonstrates the effectiveness of the proposed kinetics approach with phase change. (C) 2017 Elsevier Ltd. All rights reserved.