Study on grouting performance for underground construction in crystalline rock, 3; Numerical simulation of water-tightness improvement

Tanaka, Tatsuya*; Matsui, Hiroya ; Hashimoto, Shuji*; Ando, Kenichi*; Takeuchi, Shinji; Saegusa, Hiromitsu

This study aims to establish techniques for grouting, and evaluation of the effects of grouting on the geological environment, to be applied in the field of high level radioactive waste disposal in the deep underground. A block-scale hydrogeological model has been generated using discrete fracture networks based on data obtained from the short-borehole investigation campaign performed at the research tunnel around which grouting has been carried out. The grouting performance in terms of reducing the water inflow rate was evaluated by groundwater flow simulation. Lessons learned applicable to future studies of in-situ testing have been addressed.