Microstructure of Bentonite in Relation to its Physical Properties in Nuclear Waste Repositories.

摘要

High-level nuclear waste in Finland is planned to be placed in bedrock at a depth of several hundred meters. The spent fuel containers in boreholes drilled in the floors of deposition tunnels will be surrounded by bentonite blocks. The upper parts of the tunnels will be filled with a mixture of bentonite and crushed rock. The behavior of the bentonite around the containers during several years after deposition of nuclear waste should be predicted. In the present report, a short literature study of the microstructure of bentonite is presented. The report concentrates on bentonite MX-80. The use of stochastic imaging of microstructure was tested by using the Boolean simulation. Using stochastic imaging, the effect of changes of bentonite microstructure on its physical properties can be evaluated and predicted.