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Artificial ground freezing (AGF) is an effective technique for ground stabilization in projects such as tunneling and shaft mining. This study examines the impacts of freeze-thaw processes, soil type, and compaction levels on the strength characteristics of sandy and clayey soils and evaluates AGF performance through laboratory-scale physical modeling using liquid nitrogen as the cooling agent. Results indicate that freezing significantly enhances soil strength, but thawing leads to notable reductions. Sandy soils compacted to 95% experienced a 50% decrease in unconfined compressive strength (UCS) after brief exposure to thawing, while clayey soils exhibited a smaller reduction of 30%. Compaction emerged as a critical factor in strength retention, with UCS in sandy soils decreasing by 50% when compaction dropped from 95 to 85%, compared to a 25% reduction in clayey soils. The results also demonstrated that sandy soils froze more rapidly and efficiently, achieving a frozen diameter of approximately 25 cm around a single freezing pipe within 4 h, compared to 15 cm in clayey soils over 8 h. Furthermore, sandy soils required less liquid nitrogen to achieve the same frozen column compared to clay soils, owing to their higher thermal conductivity and lower water retention. These findings highlight the superior efficiency of AGF in sandy soils under controlled conditions, particularly when water seepage is absent, and underscore the importance of optimizing compaction levels and freeze-thaw parameters to enhance the cost-effectiveness of soil stabilization. The study provides valuable insights into soil behavior during AGF, particularly the impact of thawing, supporting its broader application in various geotechnical projects.

来源平台：GEOTECHNICAL AND GEOLOGICAL ENGINEERING