In order to demonstrate the safety of engineered barriers for radwaste geological repositories, rich characterisations of bentonite hydro‐mechanical behaviour are essential. X‐ray computed tomography was used as the single input to measure both the full displacement field and water content in a heterogeneous bentonite sample resaturated in quasi‐isochoric conditions. Since large texture changes do not allow the use of digital volume correlation, this was achieved using 3D particle tracking to provide the kinematics in combination with calibrated and beam hardening‐corrected grey levels. Matching the grey level sampling with kinematics using a mesh‐based analysis, results show the development of heterogeneous swelling inside the cell and a final solid density gradient in the direction of water flow.

中文翻译：

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使用X射线显微断层扫描和3D粒子跟踪技术同时测量膨胀粘土中的流体和固体密度

为了证明radwaste地质处置库的工程屏障的安全性，对膨润土水力学行为的丰富表征是必不可少的。X射线计算机断层扫描被用作单一输入，以测量在准等速条件下重新饱和的异质膨润土样品中的全部位移场和水含量。由于大的纹理变化不允许使用数字体积相关性，因此这是通过使用3D粒子跟踪提供运动学以及校准的和经过束硬化校正的灰度级来实现的。使用基于网格的分析将灰度采样与运动学进行匹配，结果显示了单元内部异质膨胀的发展以及沿水流方向的最终固体密度梯度。