Abstract
Safety of great deep repository design has been considered for high level radioactive waste disposal system in several countries such as Belgium, Canada, China, France, Germany, Japan, Sweden and Switzerland etc. The repository of the disposal is in most cases based on the aspect of multi-barrier system such as the natural barrier formation (i.e., host rock) and engineered barrier formation consisting of compacted bentonite. This study focuses on hydro-mechanical behavior of compacted sodium bentonite, and three different tests such as swelling test, one-dimensional compression test and constant vertical stress direct shear test were performed with suction control using vapor pressure technique. Also, a modified direct shear apparatus installed RH air circulation system was used in the direct shear test.
