Increasing understanding and confidence in THM simulations of engineered barrier systems

Previous studies on the modelling of coupled thermo-hydro-mechanical (THM) processes in bentonite-based engineered barrier systems (EBSs) showed the sensitivity of the output quantities to changes in the input parameters. To investigate the effects of uncertainties on the modelling results, to impro...

Descripción completa

Detalles Bibliográficos
Autores: Schäfers, Annika, Gens Solé, Antonio|||0000-0001-7588-7054, Rodríguez Dono, Alfonso|||0000-0002-2296-4826
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/181127
Acceso en línea:https://hdl.handle.net/2117/181127
https://dx.doi.org/10.1680/jenge.18.00078
Access Level:acceso abierto
Palabra clave:Radioactive waste disposal in the ground
Bentonite deposits
Environmental engineering
Numerical methods
Radioactive waste disposal
Abocadors de residus radioactius
Bentonita -- Propietats mecàniques
Àrees temàtiques de la UPC::Enginyeria civil::Geotècnia::Mecànica de sòls
Àrees temàtiques de la UPC::Desenvolupament humà i sostenible::Enginyeria ambiental::Tractament dels residus
Descripción
Sumario:Previous studies on the modelling of coupled thermo-hydro-mechanical (THM) processes in bentonite-based engineered barrier systems (EBSs) showed the sensitivity of the output quantities to changes in the input parameters. To investigate the effects of uncertainties on the modelling results, to improve the understanding of the coupled processes active in the repository near field and to gain in-depth understanding of model uncertainties of different codes, a sensitivity analysis and code comparison of EBS simulations was performed within the Task Force on Engineered Barrier Systems. The analysis included variations in material parameter values, boundary and initial conditions, considered physical processes and model geometries, amounting to 60 different cases. This in-depth analysis helped evaluate the influence of parameter and conceptual uncertainties on the results of coupled THM simulations and to identify key parameters and processes. The cross-code comparison encouraged a fruitful exchange among modelling teams and led to very good agreements between the results of the different codes. Serving as a benchmark example for THM-coupled simulations of bentonite-based EBSs, the study helped increase the confidence in the modelling capabilities of several codes used for safety evaluations of repositories for spent fuel and high-level radioactive waste.