We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Water Permeability Measurements by Steady-State and Pulse Decay Methods on the Callovo-Oxfordian Claystone and Impact on its Mechanical Properties.
- Authors
Grgic, D.; Moumni, M.; Giraud, A.; de La Vaissière, R.; Talandier, J.
- Abstract
This paper presents several series of multi-stage permeability tests in laboratory with both steady-state and pulse decay methods on core samples of the low permeable Callovo-Oxfordian claystone from Meuse/Haute-Marne (France). The focus is to explain why water permeability values obtained in laboratory with the steady-state method are lower than those obtained with the pulse decay method and those obtained in situ in the Underground Research Laboratory designed for a feasibility of a deep geological repository of radioactive waste. The focus is also to assess the influence of the percolating water chemistry and the duration of resaturation and steady flow stages on the permeability values, and the impact of these permeability measurements on the mechanical properties (elastic coefficients, peak strength). The water permeability values measured with the pulse decay method are homogeneous and around 10−20 m2. Those obtained with the steady flow method are significantly lower (up to one order of magnitude) when using the synthetic water of ANDRA. This difference can be explained by an additional hydration of the clay minerals during steady-state flow which induces a swelling and then a decrease of the interparticle porosity. These physicochemical mechanisms slow down the water flow during the steady flow tests. When using a chemically balanced water and reducing the test duration, the difference is only about half an order of magnitude. Sample resaturation and steady-state flow induce a significant damage of the material which is mainly due to the opening of the bedding planes of swelling clay minerals. Highlights: Laboratory permeability tests with steady state and pulse decay methods were performed on core samples of Callovo-Oxfordian claystone from Meuse/Haute-Marne (France) Permeability values measured with the steady flow method are significantly lower than those obtained from the pulse decay method when using the synthetic water of ANDRA This difference could be explained by an additional hydration of the clay minerals during steady state flow, which induces swelling and slows down the water flow A more accurate assessment of the permeability with the steady state method was obtained using a chemically balanced water and experiment with shorter run time Initial resaturation and steady state flow induce a significant damage of the material which is mainly due to the opening of the bedding planes of swelling clay minerals
- Subjects
PERMEABILITY measurement; IMPACT (Mechanics); STEADY-state flow; GEOLOGICAL repositories; CLAY minerals; RADIOACTIVE waste repositories; RADIOACTIVE waste disposal
- Publication
Rock Mechanics & Rock Engineering, 2024, Vol 57, Issue 6, p4231
- ISSN
0723-2632
- Publication type
Article
- DOI
10.1007/s00603-023-03340-0