Study on crystalline rock aiming at evaluation method of long-term behavior of rock mass; FY2013 (Contract research)

Fukui, Katsunori*; Hashiba, Kimihiro*; Sato, Toshinori  ; Sanada, Hiroyuki; Kuwabara, Kazumichi

On the radioactive waste disposal, the long-term mechanical stability of shafts and galleries excavated in rock is required. Therefore, it is very important to understand the time-dependent behavior of rock mass for evaluating long-term mechanical stability. The purpose of this study is determining the mechanisms of time-dependent behavior of rock mass by precise testing, observation and measurement in order to develop methods for evaluating long-term mechanical stability of a rock mass. This report describes the results of the activities in fiscal year 2013. In Chapter 1, we described the overview and background of this study. In Chapter 2, the results of a long-term creep test on Tage tuff, started in fiscal year 1997 are described. In Chapter 3, the result of organization and analysis for time-dependent behavior of crystalline rock was described. In Chapter 4, for the drafting of in-situ test plan, examination of the numerical analysis technique of rock mass was carried out.