円錐孔底ひずみ法における二軸感度補正法による初期応力評価への適用

In-situ stress measurement in the Mizunami Underground Research Laboratory; A New test of strain sensitivity method applying to CCBO

丹野 剛男; 佐藤 稔紀  ; 真田 祐幸; 引間 亮一*; 横山 幸也*; 下山 昌宏*

Tanno, Takeo; Sato, Toshinori; Sanada, Hiroyuki; Hikima, Ryoichi*; Yokoyama, Tatsuya*; Shimoyama, Masahiro*

瑞浪超深地層研究所の深度300mにおいて円錐孔底ひずみ法による初期応力測定を行い、従来法と二軸感度補正法による初期応力の評価を行った。両手法を比較した結果、二軸感度補正法による応力評価では、従来法による応力評価に比べて偏差応力の改善が確認され、応力値の評価について精度の向上が確認された。

rock stresses were measured by Compact Conical-ended Borehole Overcoring (CCBO) technique in the 300m depth gallery at the Mizunami Underground Research Laboratory and the measurement results were evaluated using a conventional method and a new test of strain sensitivity method. To compare the rock stress evaluated by both methods, the new test of strain sensitivity method resulted in more accurate evaluation than the conventional method, because of its improved stress deviations.