Motoshima, Takayuki*; Yabuki, Yoshio*; Minamide, Masashi*; Nago, Makito*; Aoyagi, Kazuhei
Tonneru Kogaku Hokokushu (CD-ROM), 24, p.I_10_1 - I_10_5, 2014/12
Economic tunnel support design for Horonobe underground research laboratory was obtained according to the relationship in the direction of the initial stress and the direction of excavation. The authors compared between the in situ convergence results and calculated results in order to investigate the validity of initial stress measurements. As a result, a positive correlation was observed between the in situ convergence results and calculated results, and the difference between the two was able to be explained by the difference between the assumed deformation coefficient and the measured coefficient. From these results, the measurement results of the initial stress performed in the surface based investigation has been confirmed almost reasonable.
Tsusaka, Kimikazu; Koizumi, Yu*; Tanimoto, Chikaosa*; Kameyama, Katsuhiro*; Miyajima, Yasuyuki*
Tonneru Kogaku Hokokushu (CD-ROM), 18, p.77 - 84, 2008/11
In TBM tunneling, secondary fragmentation is considered as a phenomenon that rock pieces between a cutter head and face are fragmented through the excavation process. The fragmentation should cause damage and excessive wear to the disc cutters which pass through the dome-shaped part where scrapers scoop up muck. Based on the cutter replacement records in four TBM applications through sedimentary and granitic rocks, the authors investigated the difference in the rolling distance per unit disc diameter loss between the inner cutters and the outer ones. As a result, it was clarified that the cutter life at the outer part were shorter than that at the inner part by more than 20% by the secondary fragmentation.
Hara, Masato; Kinoshita, Harunobu; Ikeda, Koki; Yamamoto, Masaru; Nobuto, Jun*
Tonneru Kogaku Hokokushu (CD-ROM), 18, p.23 - 30, 2008/11
In the excavation for the ventilation shaft of the Mizunami Underground Research Laboratory, pre-excavation grouting with ordinary Portland cement is conducted to reduce the water inflow. The target value for the hydraulic conductivity of grouted zone is set to be 2 Lugion, considering mainly the capacity of water treatment facility. In this paper, the grouting work conducted up to the depth of GL. -220m is summarized. By reviewing the water inflow and hardened cement injected into rock fractures observed at shaft wall, the validity of grouting method so far is evaluated.
Akiyoshi, Kenji*; Mikake, Shinichiro; Kaneda, Tsutomu*; Noda, Masatoshi*
Tonneru Kogaku Hokokushu (CD-ROM), 17, p.105 - 111, 2007/11
The purpose of this study grasps the effect of the solidified shape as the auxiliary method for ground improvement of deep shaft excavation in weathered rock.
Nobuto, Jun*; Fukuda, Kazuhiro*; Sato, Toshinori; Kuroda, Hidetaka
Tonneru Kogaku Hokokushu (CD-ROM), 16, p.1 - 8, 2006/11
In this paper, we examine the mechanical behavior of shaft excavated by short-step sinking method, as part of the researches to verify the applicability of engineering technologies. Concretely, the shaft behavior during excavation is analyzed with FEM to estimate the deformation and stress state of rock mass and concrete lining support. Next, we actually measure rock mass deformation around the shaft and compare them with FEM analysis results. In addition, we apply inverse analysis method to short step sinking shaft in order to understand the shaft behavior better, and finally summarize the technological points to enhance the accuracy of inverse analysis method.
Kuji, Masayoshi; Sato, Toshinori; Hara, Masato; Mikake, Shinichiro; Minamide, Masashi
Tonneru Kogaku Hokokushu (CD-ROM), 16, p.469 - 476, 2006/11
In the Mizunami Underground Research Laboratory (MIU), two 1,000m-deep shafts and several research galleries are being constructed. Water inflow into the shafts during shaft sinking is disturbing the project progress. As a countermeasure for this problem, post-grouting is being considered and post-grouting test has been undertaken in one of the shafts. This report gives an outline of the work plan and results of the post-grouting test.