2025-07-18 マサチューセッツ工科大学(MIT)
<関連情報>
- https://news.mit.edu/2025/model-predicts-long-term-effects-nuclear-waste-underground-disposal-systems-0718
- https://www.pnas.org/doi/10.1073/pnas.2511885122
放射性核種に対する複雑なバリアシステムのモデルの信頼性構築 Building confidence in models for complex barrier systems for radionuclides
Dauren Sarsenbayev, Christophe Tournassat, Carl I. Steefel, and Haruko M. Wainwright
Proceedings of the National Academy of Sciences Published:July 3, 2025
DOI:https://doi.org/10.1073/pnas.2511885122

Abstract
The modeling and simulation of the Cement–clay Interaction–Diffusion field (CI-D) experiment at the Mont Terri site in Switzerland presented here demonstrates that it is possible to capture the multiscale physical and chemical features of natural and engineered barrier systems for radionuclides. The simulations are successfully carried out with the newly developed CrunchODiTi high-performance computing software that accounts for multiple continua, including a continuum representing the electrical double layer (EDL) developed along negatively charged clay particles in clay rock. The simulation also accounts for both the complex three-dimensional (3D) geometry, expected as the norm in a geological waste repository, and the anisotropy of the geological formation. In addition, the high resolution of the model makes it possible to include “skin effects” developed at the interface between highly reactive materials, in this case between the high pH cement and the circumneutral but electrostatic Opalinus Clay. The successful history matching with the field experiment demonstrates that the distinct geochemical and physical properties of the cement and the Opalinus Clay in the CI-D experiment can be accounted for. Such analyses are essential for developing a defensible safety case for the underground storage of radioactive waste.


