Abstract:In order to clarify the quantitative relationship between the moisture vertical migration and the main influencing factors during soil freezing-thawing process, a unidirectional freezing-thawing simulation test was carried out using typical black soil in Northeast China, under the conditions of different initial moisture contents, temperature drop ranges, and groundwater levels. The results showed that: (1)The temperature changes in the samples were fast first and then slow, and the internal temperature of the samples showed a stable temperature gradient distribution with the variations of the depths. (2) The influence of initial moisture content on soil freezing was obvious. The higher the initial moisture content of soil was, the longer the duration of freezing process was, and the larger the latent heat consumed in the freezing process was, and the later the formation time of freezing front was. (3) Various temperature drop ranges caused the obvious difference of soil temperature gradients. The migration of water in the vertical direction was the largest with the temperature changes at 15 ℃, the soil entered the freezing stable stage at fastest speed, and the moisture content near the 20 cm soil layer reached the peak value after 16 hours. (4) The higher the groundwater level was, the smaller the temperature difference was, the slower the downward migration rate of the freezing front was. The water content in each layer increased significantly, and accumulated in the upper and middle layers.