Simulation of the degradation of a concrete/clay interface:influence of temperature, unsaturated conditions and porosityvariations
For long-lived intermediate-level radioactive waste, the useof concrete as engineering barrier and Callovian-Oxfordian clay asgeological barrier at a depth of 500 m is considered in the Frenchdisposal concept (ANDRA, 2005). Upon emplacement, initially unsaturatedconcrete is expected to experience coupled processes involving heating,re-saturation with groundwater from the clay formation, gas exchanges andgeochemical reactions. After an early period of re-saturation, solutetransport is supposed to be diffusion-controlled because of the extremelylow permeability of the two media. These coupled processes may lead tochanges in the porosity of the concrete or clay barriers. In the presentpaper, a fully coupled Thermo-Hydro-Chemical (THC) response of atwo-phase (gas and solution) mass-transfer model was evaluated and testedby a sensitivity analysis. This study is an extension of a previous modelapplied to an isothermal and fully saturated concrete/clay interface(Burnol et al., 2005); it investigated the coupled effect of temperatureand unsaturated conditions assuming no production of H2(g). The systemwas simulated for a 2000-year period, which covers the most predominantthermal perturbation.
- Research Organization:
- COLLABORATION -BRGM/France
- DOE Contract Number:
- DE-AC02-05CH11231
- OSTI ID:
- 928238
- Report Number(s):
- LBNL-63365; R&D Project: G60691; BnR: DF0961000; TRN: US0804306
- Resource Relation:
- Conference: 3rd International Meeting on Clays in Natural&Engineered Barriers for Radioactive Waste Confinement, Lille,France, 17-20 September 2006
- Country of Publication:
- United States
- Language:
- English
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