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本文利用ＣＴ对岩石、土壤、水体多种成分的冻结过程进行了实验研究。阐述了Ｘ射线与物质的相互作用，ＣＴ检查实验样品的数学原理。对图像的分辨率和伪影进行了讨论，对实验样品的最佳扫描条件进行了分析。为了定量分析岩土ＣＴ图像，以便深人地动态研究在不同实验过程中土样内部组织结构的变化，物质成份的迁移，需要针对扫描样品建立数值方程。通过对各种形状、尺寸、密度和组分的标准样品进行大量的ＣＴ扫描，对理论方程进行了验证。对扫描数据的统计分析说明，ＣＴ值随物质密度增加而线性增加，其斜率与物质成份有关；对于高密度的物质，ＣＴ值随着样品直径的减小而增加。为了以统一的数学模型描述实验样品的ＣＴ值，对理论公式进行调整、建立了半经验数值方程。利用数值方程可以定量分析岩土样品在冻结过程中的水份迁移，冻结澎胀变形；在外力作用下组织结构的变化；在温度变化过程中在冻结层面及未冻水的含量；在自然状态中材料的孔隙度等等工程科学研究中的问题。实验证明，ＣＴ用于岩土及其它材料科研中具有较高的价值。
In this paper, experimental studies on the freezing process of various components of rock, soil, and water were conducted using CT. The interaction between X-rays and matter is described. The mathematical principle of the CT examination of the experimental sample is described. The resolution and artifacts of the image are discussed, and the optimal scanning conditions of the experimental sample are analyzed. In order to quantitatively analyze the geotechnical CT images in order to deeply and dynamically study the changes in the internal structure of the soil samples and the migration of material components during different experiments, numerical equations need to be established for the scanned samples. A large number of CT scans were performed on standard samples of various shapes, sizes, densities and compositions to verify the theoretical equations. The statistical analysis of the scan data shows that the CT value increases linearly with increasing material density, and the slope is related to the composition of matter; for high density materials, the CT value increases as the sample diameter decreases. In order to describe the CT value of the experimental sample with a unified mathematical model, the theoretical formula was adjusted and a semi-empirical numerical equation was established. The numerical equations can be used to quantitatively analyze the water migration, freezing and swell deformation of frozen rock samples during freezing, change the structure of the structure under external forces, and freeze levels and unfrozen water during temperature changes. The porosity of medium materials, etc. Experiments have proved that CT is of high value in the research of rock and other materials.