New model for hydraulic conductivity of frozen soils

One of the core issues in studying the problems such as frost heave and thaw weakening in cold regions is the process of hydro-thermal coupling migration. Determination of the hydraulic conductivity of frozen soils is the critical point to understand this process. Different from that of soils at positive temperatures, the hydraulic conductivity of frozen soils involves the liquid water flow in soil grains and ice particles. How to better express the hydraulic conductivity of frozen soils is an outstanding issue in the literatures. In this study, a new hydraulic conductivity model for frozen soils is proposed on the basis of a derivation process of the Kozeny-Carman equation, which is consistent to the determination of hydraulic conductivity at positive temperatures. By comparing with the models in the literatures and experimental data, the model in this study can match the experimental data well, which verifies the rationality of the proposed model. Compared with the existing empirical models or the mathematical models in the literatures, this model has only one fitting parameter. Besides the proposed model has a clear physical basis and is simple in form, which is easy to apply.