Abstract
In high-level radioactive waste disposal facilities, buffer and backfill materials play a crucial role as hydraulic and radionuclide barriers and as thermal-mechanical barrier materials. The performance of bentonite-based buffer-backfill samples subjected to hydration was analyzed. Four cylindrical samples with the same upper buffer material, and different lower backfill materials were subjected to a constant water pressure of 10 psi. The swelling pressure was recorded continually, while X-ray CT scanning were taken periodically to follow the internal evolution of the samples. The initial density, porosity, and swelling ability of the backfill influenced the hydration process and the buffer-backfill interface displacement.
https://ror.org/01v7y5b55 
