Relevance of adopting a double porosity retention curve for modelling bentonite hydration under high temperature conditions
This study aims to gain a better understanding of the coupled thermo-hydraulic effects of the water retention formulation in compacted bentonites, and especially of a double porosity formulation. To this end, several thermo-hydraulic laboratory tests have been simulated with a thermo-hydro-mechanica...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2025 |
| País: | España |
| Institución: | Universidad de Castilla-La Mancha |
| Repositorio: | RUIdeRA. Repositorio Institucional de la UCLM |
| OAI Identifier: | oai:ruidera.uclm.es:10578/43630 |
| Acceso en línea: | https://doi.org/10.1016/j.gete.2025.100684 https://hdl.handle.net/10578/43630 |
| Access Level: | acceso abierto |
| Palabra clave: | Bentonite Double porosity Modeling Radioactive waste disposal Thermo-hydraulic coupling Water retention |
| Sumario: | This study aims to gain a better understanding of the coupled thermo-hydraulic effects of the water retention formulation in compacted bentonites, and especially of a double porosity formulation. To this end, several thermo-hydraulic laboratory tests have been simulated with a thermo-hydro-mechanical model using three different water retention formulations: single porosity, single porosity with temperature dependence and double porosity. The results indicate that the impact of including temperature dependence in a single porosity model is limited. In addition, for the case that combines intense heating (150 ºC) with hydration, only the double porosity model produced quality results, even if it did not include a direct dependence on temperature. Differentiation between microstructural and macrostructural water is key to reproducing the thermally induced drying and exhaustion of the flow channels observed in these conditions and not under moderate heating. Therefore, double porosity formulations for the water retention behaviour of bentonites are especially advisable to represent the coupled thermo-hydraulic effects in conditions combining intense heating with hydration, as in deep geological repositories of spent nuclear fuel. |
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