Advances in Computed Tomography for Geomaterials: GeoX 2010

Deformation in Fractured Argillaceous Rock under Seepage Flow Using X-ray CT and Digital Image Correlation

D. Takano¹ — P. Bésuelle¹ — J. Desrues¹ — S. A. Hall¹

¹Laboratoire 3S-R, CNRS and University GrenobleBP 53, 38041, Grenoble, [e-mail]

ABSTRACT. Argillaceous rock is a candidate for radioactive waste storage because of its extremely low permeability. However, during excavation of storage galleries, drilling can induce fractures that may modify (generally increase) the rock permeability. On the other hand, it is thought that stress redistribution after drilling and fluid seepage through time can lead to, at least partial, closure of these fractures. A number of studies reported previously have evaluated the changes in sealing capacity of these fractured argillaceous rocks, but such studies are mostly limited to 2D experiments or numerical modeling, and there are relatively few studies that consider the 3D behavior. The purpose of this paper is to evaluate, using x-ray computed tomography and 3D-volumetric Digital Image Correlation (DIC), the 3D deformation distribution in specimens of fractured argillaceous rock experiencing seepage flow. To achieve this, x-ray tomography images have been acquired of fractured rock specimens at several different stages of seepage flow experiments and 3D-DIC has been applied to evaluate the 3D displacement and strain fields. With ...