Variation characteristics of hydrothermal state and migration laws of water and salt in Qarhan Salt Lake region

In order to improve the engineering stability of saline soil with high chloride content in Qarhan Salt Lake region, the hydrothermal and evaporation variations for many years in this region are analyzed. The air temperature and geotemperature in cold season as well as and the water content and salt content at different depths are tested and studied. The results show the characteristics of the monthly average temperature and geotemperature difference variations, temperature difference between day and night geotemperature variations, time-history and transfer variations of the monthly average geotemperature. A regression equation for the temperature with time and depth of the heat transfer capacity and transmission rate is derived. The thermal effect of the soil is the dominant factor for water and salt migration, and the thermal-effect reaction decreases with the increase of the soil depth. For this reason, two salt accumulation areas in the surface and 1 m -2.5 m under the surface are formed, and the design and construction of future projects in saline soil should take it into account.