| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an artificial barrier structure capable of removing an overpack from a buffer material without newly generating radioactive waste, safely in a short time.SOLUTION: A disposal gallery having a diameter of about 5 m is constructed in a rock bed functioning as a natural barrier at several hundred meters below ground, and a disposal hole having a diameter of about 2 m is formed vertically below the disposal gallery. Then, a bottomed cylindrical separation container 33, which is installed in an inner space of the disposal hole, which is composed of a bottom part 34 and a peripheral wall part 35 erected from its circumferential edge, and in which an upper edge 36 of the peripheral wall part forms an opening 38, is buried in a buffer material 22 made of bentonite so as to surround an overpack 32 while the peripheral wall part 35 is separated from a peripheral surface of the overpack. The bottom part 34 of the separation container 33 is formed so as to block tension load transfer in its thickness direction. Similarly, the peripheral wall part 35 is formed so as to block shear load transfer in a direction orthogonal to the thickness direction.</p> |
