The thermophysical properties of soil are crucial factors for understanding the heat distribution in soil layers, especially in cold regions. Therefore, to analyze the effect of freezing and thawing action on soil thermophysical properties, here, samples with varying water content were subjected to different numbers of freezing and thawing cycles from 0 to 11 in a laboratory setting, and the thermal conductivity, thermal diffusion coefficient and volume heat capacity were measured and analyzed. Five previously proposed thermal conductivity models were evaluated, and a novel thermal conductivity model was developed based on the concept of the tortuosity and parallel model. The results showed that the thermal conductivity and volume heat capacity vary in direct proportion with the number of freezing and thawing cycles up to seven cycles. Beyond seven cycles, with repeated freezing and thawing action, samples with varying water content reach a residual porosity ratio of 0.5142–0.5345. Both the water content and freezing and thawing action influence the soil thermophysical properties, with water content playing a more important role than freeze–thaw cycles. Among these five models, the Kersten model was found to be the best, followed by the Johansen model, Lu et al. model, parallel model, and serial model. respectively. The Cote and Konrad model demonstrated the poorest performance. In addition, the tortuosity–parallel model was able to efficiently calculate the thermal conductivity of clay under freezing and thawing action.

中文翻译：

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反复冻融条件下粘土热物理性质的研究

土壤的热物理特性是了解土壤层中热量分布的关键因素，特别是在寒冷地区。因此，为了分析冻融作用对土壤热物理性质的影响，这里，在实验室环境中对不同含水量的样品进行了从 0 到 11 次不同数量的冻融循环，以及热导率、热扩散系数和体积热容量进行了测量和分析。对五个先前提出的热导率模型进行了评估，并基于曲折和平行模型的概念开发了一种新的热导率模型。结果表明，热导率和体积热容随冷冻和解冻循环次数成正比变化，最高可达7次。超过 7 个循环，通过反复冻融作用，不同含水量的样品达到 0.5142-0.5345 的残余孔隙率。含水量和冻融作用都会影响土壤热物理特性，含水量比冻融循环起着更重要的作用。在这五个模型中，发现 Kersten 模型最好，其次是 Johansen 模型，Lu 等人。模型、并行模型和串行模型。分别。Cote 和 Konrad 模型表现出最差的性能。此外，曲折平行模型能够有效地计算粘土在冻融作用下的热导率。含水量和冻融作用都会影响土壤热物理特性，含水量比冻融循环起着更重要的作用。在这五个模型中，发现 Kersten 模型最好，其次是 Johansen 模型，Lu 等人。模型、并行模型和串行模型。分别。Cote 和 Konrad 模型表现出最差的性能。此外，曲折平行模型能够有效地计算粘土在冻融作用下的热导率。含水量和冻融作用都会影响土壤热物理特性，含水量比冻融循环起着更重要的作用。在这五个模型中，发现 Kersten 模型最好，其次是 Johansen 模型，Lu 等人。模型、并行模型和串行模型。分别。Cote 和 Konrad 模型表现出最差的性能。此外，曲折平行模型能够有效地计算粘土在冻融作用下的热导率。分别。Cote 和 Konrad 模型表现出最差的性能。此外，曲折平行模型能够有效地计算粘土在冻融作用下的热导率。分别。Cote 和 Konrad 模型表现出最差的性能。此外，曲折平行模型能够有效地计算粘土在冻融作用下的热导率。