Abstract:Frozen soil is widely distributed in China. As a common problem in frozen soil areas, frost heave frequently causes engineering diseases. Frost heave, which is mainly formed by the temperature change and water migration in the soil during freezing and thawing, is an extremely complex multifield coupling problem of temperature, seepage, and stress. In this paper, the general transient heat conduction equation of frozen soil under the changes of ice content and porosity with temperature was solved by analyzing the temperature field in frozen soil, and its approximate analytical solution was obtained and applied to predict the heat conduction process of frozen soil. Compared with the exact solution obtained from finite element calculation, the effectiveness of the analytical solution was verified. The research results show certain theoretical and practical significance for the intensive study of the problem of frost heave in frozen soil.