Influence of Water Saturation on Curtain Formation of Frozen wall

Abstract

Abstract In the process of in-situ mining of underground oil shale, underground Frozen wall are often used for water seal and wall retaining, And the water saturation of the frozen soil affects the formation of the freezing circle. Using the methods of theoretical analysis, Indoor similar simulation test and numerical simulation to be obtained the temperature drop process and freezing time around the Frozen wall under different water saturation conditions, and use finite element software for simulation verification. The experimental and simulation results show that:1) With the increase of water saturation, the longer the freezing time at the center of the connection line of the Frozen wall, the more difficult is to form the Frozen wall closure, and the worse the freezing effect is; 2) The temperature change trend of the center point is different under different water saturation, the higher the water saturation, the slower the initial temperature decline rate, when the water saturation is 100%, the initial temperature drop hysteresis phenomenon occurs, and the Frozen wall closure begins to form gradually until 192.4 min in the experiment; With the increase of water saturation, the influence range of the two Frozen walls in the model gradually decreases at the same time. Therefore, the groundwater content (quantitative result) has a great influence on the formation time of the Frozen wall, the research results can provide reference for the design of underground Frozen wall in high-temperature mining of oil shale.