A Grouting methodology in hard rock; Research on grouting in Mizunami Underground Research Laboratory, 1

Mikake, Shinichiro ; Sato, Toshinori  ; Nobuto, Jun*; Akita, Tetsushi*; Nishigaki, Makoto*

In radioactive waste disposal, grouting technology is expected to reduce ground water inflow, not only to execute construction and operation securely in deep underground and protect surrounding environment, but also to secure barrier capacity. Here, a grouting methodology is studied to achieve high-level sealing effect in disposal tunnels in hard rock by pre-grouting, by reviewing grouting methodologies utilized in water tight tunnels in Northern Europe. The result indicates that boring injection holes shortly and densely is superior in sealing efficiency and economical view point.