Abstract The influence of dry-wet change process on rock thermal conductivity is the key to many geological and engineering issues, especially for rocks with high clay mineral content. In this study, sandstone with different clay mineral contents were subjected to different treatment processes, namely drying, wetting and drying II, and their thermal conductivity were measured through the hot wire method. The results indicate that the thermal conductivity of the samples subjected to the drying II treatment was significantly lower than that of the samples subjected to the drying treatment, and the magnitude of the decrease was related to the clay mineral content in the samples. Moreover, using the effective thermal conductivity calculation model that considers microcracks, it is found that the main reason for the decrease in the thermal conductivity of sample is the large number of secondary cracks generated in sample during the wetting-drying process. According to the pore structure and the microstructure of the samples under different state, it is speculated that the dissolution of soluble minerals, disintegration of minerals, swelling and shrinking of clay minerals are the possible causes of cracks in the sample during the wetting-drying process.

中文翻译：

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含粘土砂岩不同处理工艺热导率实验研究：干湿干二

摘要 干湿变化过程对岩石热导率的影响是许多地质和工程问题的关键，特别是对于粘土矿物含量高的岩石。本研究对不同粘土矿物含量的砂岩进行干燥、润湿、干燥Ⅱ等不同处理工艺，采用热丝法测量其热导率。结果表明，经过干燥II处理的样品的热导率明显低于经过干燥处理的样品，并且降低的幅度与样品中粘土矿物的含量有关。此外，利用考虑微裂纹的有效导热系数计算模型，发现样品热导率下降的主要原因是样品在干湿过程中产生的大量二次裂纹。根据不同状态下样品的孔隙结构和微观结构，推测可溶性矿物的溶解、矿物的解体、粘土矿物的膨胀和收缩是造成干湿过程中样品出现裂纹的可能原因。 .