Soil Freezing with Shallow Water Table Depth: Experiment and Simulation

For better understanding the relationship between shallow water table depth and soil freezing, 4 identical soil columns were prepared for experiments with 60-cm initial water table depth, as well as for sampling at 4 different periods during soil freezing(0, 3, 5, 7d). Flux model was built to analyze the water and salt transport with shallow groundwater recharge, based on water and salt balance in each soil layer. Results indicated that water and salt move upward simultaneously and accumulate near the freezing front with recharge, resulting in peak values of water and salt flux at some depths. Because of the recharge of shallow groundwater, the total water content in the soil column increased, and the penetration of freezing front was blocked as a result of the thermal redistribution in the frozen zone. A capillary bundle for water flux determination in frozen soil was used to simulate the water flux during soil freezing, and the water flux calculated by flux model was compared with capillary bundle simulating results, indicating that flux model could depict the water flow in frozen soil reasonably.