CT用于动态观察土体内部结构发育过程的试验研究

AN EXPERIMENTAL STUDY ON DYNAMICAL OBSERVATION ON THE EVOLUTION OF INTERNAL FAILURES IN SOIL MODELS USING COMPUTERIZATION X-RAY TOMOGRAPHY (CT)

CT技术已在土壤科学和岩石力学等学科中得了应用 ,但还未广泛应用于地理和地质分析中 .为了探索CT技术在动态观察地质体内部结构变化的可行性 ,设计和研制了一个能适用于CT观察仓的推力装置 ,对两种土体模型 :一种是由砂子和硅粉组成的散粒体模型 ;另一种由面粉和高岭土组成的塑性模型进行了平推试验 .试验中土体模型中内部结构的变化过程 ,用CT进行了连续拍摄 ,分析和讨论了这些观察结果 .试验表明 ,CT作为一个强有力的无损伤和无侵入的观察工具 ,可以研究一般情况下无法观察到的土体内部结构的变化过程 ,是地理和地质分析方面一个十分先进的研究手段 .

Computerized X ray Tomography (CT) has been used in disciplines such as soil science and rock mechanics to analyze the texture of geomaterials. However, this potential method has not thus far been used adequately in geological analyses. CT is utilized in this study to monitor the evolution of internal failures in soil masses. An apparatus that can be fitted into the chamber of a medical CT is built to conduct geotechnical tests. The horizontal loading experiments are performed on two kinds of soil models: one consists of dry sand and silicon powder; another is made of kaolinite powder and wheat powder with a certain water content. CT images are taken on different cross sections inside the specimens to monitor soil deformation continuously. The test results are presented and discussed. It has been demonstrated that CT is a powerful non destructive and non invasive tool for geographical and geological analyses.