Comparison of THM-Controlled Centrifugal Model Tests and Numerical Simulations for Evaluating Long-Term Stability in HLW Geological Disposal
Comparison of THM-Controlled Centrifugal Model Tests and Numerical Simulations for Evaluating Long-Term Stability in HLW Geological Disposal
For geological disposal of high-level radioactive waste (HLW), it is necessary to evaluate the long-term stability of the near field (the area surrounding the HLW disposal hole) following the emplacement of waste in deep underground bedrock. Therefore, attempts have been made to significantly shorten the time required for testing static physical phenomena using centrifugal model tests and to enhance the reliability of long-term near-field stability evaluations by comparing the results of centrifugal model tests with those of numerical models. However, controlling and measuring the heat, pore water, and stresses in scaled models of 1/30 or 1/50 used in centrifugal model tests tends to be technically challenging. In this study, we devised test vessels and scaled models to simulate heat generation from waste, and designed a test to obtain time-dependent changes in water infiltration and stress in the buffer material, enabling comparisons with thermal-hydraulic-mechanical simulations. Water tended to percolate from the outside to the vicinity of the heated overpack, and the numerical analysis reproduced the near-field behavior.
M. SATO; Masataka Sawada; Soshi Nishimoto
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 5: Combination of numerical and physical modelling
https://doi.org/10.53243/ICPMG2026-332