A Deep-Cooling Emergency Sealing Device for Artificial Ground Freezing Systems and Its Application Performance

Traditional emergency treatments for sudden water inrush during Artificial Ground Freezing (AGF) often involve substantial disturbance to the surrounding ground and high operational costs. To address these limitations, this study analyzes the disaster-chain mechanism underlying seepage-induced frozen-wall failure and proposes a rapid intervention strategy. A dedicated Rapid Sealing Equipment (RSE) was developed, and its feasibility and effectiveness were evaluated through physical model experiments and numerical simulations. The results show that the RSE, utilizing the ultra-low temperature of liquid nitrogen, can efficiently seal seepage channels in damaged frozen soil. Its sealing performance is predominantly controlled by the RSE cooling temperature ( T ln ), seepage-channel radius ( r w ), and initial soil temperature ( T s ), in descending order of influence: T ln > r w > T s . Moreover, the thermal influence of the RSE on the surrounding soil can be effectively managed by adjusting the duration of deep cooling. Based on these findings, a set of recommended design parameters for the RSE is proposed to guide practical applications in AGF emergency response.