Method for calculating the liquid water fraction of saline soil during the freezing process

Abstract

AbstractThe liquid water fraction is one of the most important parameters in the study of saline soils of cold regions, and has great influence on water migration. The freezing temperature and saturated concentration of pore solutions have been investigated according to thermodynamic theory, indicating that pore radius, temperature, and salt concentration are the three main influencing factors. Here, a method for calculating the liquid water fraction of saline soil is proposed, in which the liquid water fraction of saline soil can be calculated for different water contents and initial salt concentrations according to the pore size distribution. Comparison of the experimental data with the results of the model shows that the model provides reasonable calculations for the unfrozen water content of saline frozen soils, and both the first and the second phase transition can be modeled well. Considering the solubility of salt, the amount of salt crystallization and ice formation during cooling can also be obtained. The proposed method can be used to distinguish the proportion of salt expansion and frost heave, and also provide a novel approach for calculating the matric suction of saline soil during the freezing process.