Studies on the reconstruction of the concept of rock mass around the tunnel; Japanese fiscal year, 2014 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Aoki, Kenji*; Tochiyama, Osamu*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Yoshida, Hidekazu*; Murakami, Hiroaki; Sasao, Eiji

JAEA-Research 2015-017, 54 Pages, 2015/12

JAEA-Research-2015-017.pdf:17.3MB

This report is concerned with research to reconstruct more realistic near-field (NF) concept for the geological disposal of radioactive waste. This year is the final year of this committee activities. So we have carried out the summary on Re-thinking of NF concept and its technical basis. Cooperation between the study fields and combination of various science and technology and evaluation methods are one of the important technical bases of NF concept. In addition, since the "Great East Japan Earthquake 2011", the safety paradigm has shifted dramatically. In the reconstruction of realistic NF concept, it is necessary to analyze what security matters whether society has become unacceptable for geological disposal. Committee, we also exchange views on such matters and presented the direction of future research and development for geological disposal.

Studies on the reconstruction of the concept of rock mass around the tunnel; Fiscal year, 2012 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Aoki, Kenji*; Tochiyama, Osamu*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Yoshida, Hidekazu*; Ogata, Nobuhisa

JAEA-Research 2013-015, 21 Pages, 2013/11

JAEA-Research-2013-015.pdf:10.41MB

This report is concerned with research to reconstruct more realistic near-field concept for the geological disposal. In chapter, we examined the realistic concept for near field, including rock around the tunnel, based on the nuclide migration scenario in particular. The time-series change of the field was divided into five stages of 0IV through the process of geological disposal (Excavation, Operation and Post-closure). Then, for each stage respectively, we examined interaction between environmental factors and extraction of those factors changing the "field". The Goal of this year is to set up the state in the realistic "field" exhaustively, by focusing on the scale-time cross-section of each stage, especially post-closure stage, and to present the assignment of the next fiscal year.

Study on systemizing of technology for investigation and analysis of the deep underground geological environment; Japanese fiscal year, 2009 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Watanabe, Kunio*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Shimada, Jun*; Aoki, Kenji*; Tochiyama, Osamu*; Yoshida, Hidekazu*; Ogata, Nobuhisa; et al.

JAEA-Research 2010-049, 282 Pages, 2011/02

JAEA-Research-2010-049.pdf:29.88MB

This report summarizes studies that have been carried out with the aim of assessing and systemizing the technology used for the investigation and analysis of the deep underground geological environment in relation to the disposal of radioactive waste. The main studies were: (1) a study on the research and development (R&D) topics proven to have practical application for the investigation, and analysis and understanding of the deep underground geological environment, and, (2) a study on leading edge technology that can provide the advanced technical basis for the investigation, analysis and understanding of the deep underground geological environment. Regarding the R&D topics (1, above), specific investigations, measurements, numerical analyses and chemical analyses were performed and reviewed with respect to the topics, (a) Repository design, engineering technology (b) Geological environment and (c) Safety evaluation. Based on the result of the review, topics requiring collaboration research in overlapping research fields, including safety assessment, were identified. Also, the near field concept (NFC) was reconsidered in terms of its realistic construction model. Regarding advanced technology (2, above), based on the objectives of the JAEA (Japan Atomic Energy Agency) research project, the study was implemented considering previous R&D results and detailed research result at the research site and thus an assessment of the need for advanced technical basis for investigation and analysis. This study contributed to the R&D development and its practical application.

Study on systemizing technology on investigation and analysis of deep underground geological environment; Japanese fiscal year, 2007 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Watanabe, Kunio*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Shimada, Jun*; Aoki, Kenji*; Tochiyama, Osamu*; Yoshida, Hidekazu*; Ogata, Nobuhisa; et al.

JAEA-Research 2008-099, 171 Pages, 2009/03

JAEA-Research-2008-099-1.pdf:28.65MB
JAEA-Research-2008-099-2.pdf:49.14MB

In this year, the following studies were carried out with the aim of systemizing the technology on the investigation and analysis to understand the deep underground geological environment in relation to the radioactive waste disposal. (1) The study on the research and development (R&D) subjects which turned to the practical investigation and analysis of deep underground geological environment. (2) The study on the advanced technical basis for the investigation and analysis of deep underground geological environment. The results obtained from the studies are as follows: Regarding (1), the specific investigations, measurements, numerical and chemical analyses were performed particularly for research subjects: (a) the repository design and engineering technology and (b) geological environment. Based on the results on (1), (c) tasks of collaboration research on niche area between the research fields, including the safety assessment field, were selected. Also subject's items of the NFC (Near Field Concept) redefinition were discussed. Regarding (2), based on the extraction tasks of JAEA (Japan Atomic Energy Agency) research project, the study was implemented with applying previous R&D results and detailed research at the research field was carried out. This study contributed to the R&D development for its practical application.

Study on systemizing the technology on the investigation and analysis of deep underground geological environment; Japanese fiscal year, 2006 (Contract research)

Kojima, Keiji*; Onishi, Yuzo*; Watanabe, Kunio*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Shimada, Jun*; Aoki, Kenji*; Tochiyama, Osamu*; Yoshida, Hidekazu*; Ogata, Nobuhisa; et al.

JAEA-Research 2007-060, 210 Pages, 2007/09

JAEA-Research-2007-060-1.pdf:43.82MB
JAEA-Research-2007-060-2.pdf:41.2MB
JAEA-Research-2007-060-3.pdf:6.42MB

The following study was done with the aim of systemizing the technology on the investigation and analysis to grasp deep underground geological environment in relation to the radioactive waste disposal. (1) The study on the research and development (R&D) subjects which turned to the practical investigation and analysis of deep underground geological environment. (2) The study on the advanced technical basis of the investigation and analysis of deep underground geological environment. It continued in the former year and got the following results. Concerning (1), the concrete investigation, measurements, numerical analyses and chemical analyses were enforced about the following item and extracted some subjects with the viewpoint of radioactive waste disposal. More over, the way to make the co-operative program among each field of the following (a), (b) and (c) was discussed. (a) The subjects extracted with the viewpoint of the repository design and engineering technology. (b) The subject extracted with the viewpoint of the safety assessment. (c) The subjects extracted with the viewpoint of the geological environment. The joint research subjects among each field of (a), (b), (c) were also discussed. Concerning (2), the evaluation of the results and a way to the practical use were discussed on the R&D activities. The Study group also discussed and gave the comment on the 2nd stage of the MIU (Mizunami Underground Research Laboratory) research program in the JAEA.

Study on Systemizing the Technology on the Investigation and Analysis of Deep Underground Geological Environment, 2003

Kojima, Keiji*; Onishi, Yuzo*; Watanabe, Kunio*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Shimada, Jun*; Aoki, Kenji*

JNC TJ7400 2004-008, 234 Pages, 2004/02

JNC-TJ7400-2004-008.pdf:11.02MB

The following was done in this year with the aim of systemizing the technology on the investigation and analysis to grasp deep underground geological environment in relation to the radioactive waste disposal. (1) The study to extract the research and development (R&D) subjects turned to the practical investigation and analysis of deep underground geological environment. (2) The study on the advanced technical basis of the investigation and analysis of deep underground geological environment. It continued in the former year and got the following results. Concerning (1), the concrete investigation, measurement and numerical / chemical analysis were enforced about the following item and extracted some subjects with the viewpoint of radioactive waste disposal. 1: The subjects extracted with the viewpoint of the repository design and engineering technology. *The evaluation technique of the excavation disturbed zone (EDZ) by acoustic emission (AE) or micro seismicity measurement. *Fracture sealing technique such as vibration grouting toward low permeable rock mass. 2: The subject extracted with the viewpoint of the safety assessment. *Precipitation of the metal hydroxide (non-crystallized) through migration process in rock mass and change to the crystallized oxide.3: The subjects extracted with the viewpoint of the geological environment. *Fracture distribution characteristics around the fault, it can think to meet in the underground facilities and the prediction of long term activities of the fault. *Natural sealing process by the secondary filling materials (iron oxide and carbonate etc.) in the fracture of rock mass and that influence which may be given to the long-term migration and release of nuclides. The advanced research subjects among the each field of 1, 2, 3 were also discussed. Concerning (2), the evaluation of the results and a way to the practical use were discussed on the R&D activities of the following item.

Examination of realistic conceptual model of near-field process in HLW repository

Yoshida, Hidekazu*; Kojima, Keiji*; Onishi, Yuzo*; Tochiyama, Osamu*; Nishigaki, Makoto*; Tosaka, Hiroyuki*; Sugihara, Kozo; Ogata, Nobuhisa

no journal, , 

no abstracts in English