Homogenization of engineered barriers, simulations verified against Canister Retrieval Test data

The homogenization process in a buffer of KBS-3 design is here studied. An analytical model capable of predicting the average void ratios at full water saturation in the bentonite block and pellet slot is presented. It is found that pressure difference between the block and pellet slot together with the character of the wetting governs the homogenization. Simulations of the Canister Retrieval Tests experiment, using both the finite element solver Code-Bright and the analytical model show that the models agree well with the experimental data. The obtained responses when simulating two extreme wetting scenarios, fast or slow wetting, using Code-Bright and the analytical model also show good agreement. (authors)