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Mizuno, Rurie*; Niikura, Megumi*; Saito, Takeshi*; Matsuzaki, Teiichiro*; Sakurai, Hiroyoshi*; Amato, A.*; Asari, Shunsuke*; Biswas, S.*; Chiu, I.-H. ; Gianluca, J.*; et al.
Nuclear Instruments and Methods in Physics Research A, 1060, p.169029_1 - 169029_14, 2024/03
Times Cited Count：0 Percentile：0.02(Instruments & Instrumentation)Nakayama, Masashi; Saiga, Atsushi; Kimura, Shun; Mochizuki, Akihito; Aoyagi, Kazuhei; Ono, Hirokazu; Miyakawa, Kazuya; Takeda, Masaki; Hayano, Akira; Matsuoka, Toshiyuki; et al.
JAEA-Research 2019-013, 276 Pages, 2020/03
JAEA-Research-2019-013.pdf:18.72MB
The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies for geological disposal of High-level Radioactive Waste through investigations of the deep geological environment within the host sedimentary rock at Horonobe Town in Hokkaido, north Japan. The investigations will be conducted in three phases, namely "Phase 1: Surface based investigations", "Phase 2: Construction phase" (investigations during construction of the underground facilities) and "Phase 3: Operation phase" (research in the underground facilities). According to the research plan described in the 3rd Mid- and Long- term Plan of JAEA, "Near-field performance study", "Demonstration of repository design option", and "Verification of crustal-movement buffering capacity of sedimentary rocks" are important issues of the Horonobe URL Project, and schedule of future research and backfill plans of the project will be decided by the end of 2019 Fiscal Year. The present report summarizes the research and development activities of these 3 important issues carried out during 3rd Medium to Long-term Research Phase.
Aoyagi, Kazuhei; Chen, Y.*; Ishii, Eiichi; Sakurai, Akitaka; Miyara, Nobukatsu; Ishida, Tsuyoshi*
JAEA-Research 2019-011, 50 Pages, 2020/03
JAEA-Research-2019-011.pdf:3.48MB
In this research, we performed the resin injection experiment at the 350 m Gallery of Horonobe Underground Research Laboratory in order to identify the distribution of fractures induced around the gallery owing to excavation. We also observed the rock cores obtained around the resin injection borehole under ultraviolet light. As a result, the extent of the development of EDZ fracture was 0.9 m from the gallery wall. In the depth within 0.4 m from the gallery wall, the density of the EDZ fracture is higher than the depth more than 0.4 m from the gallery wall. As a result of the analysis on the fracture aperture by image processing, the fractures with a large aperture (1.02 mm in maximum) were observed within 0.3 m from the gallery wall, while the maximum aperture was 0.19 mm in the depth more than 0.3 m from the gallery wall.
Aoyagi, Kazuhei; Chen, Y.*; Ishii, Eiichi; Sakurai, Akitaka; Ishida, Tsuyoshi*
Proceedings of 5th ISRM Young Scholars' Symposium on Rock Mechanics and International Symposium on Rock Engineering for Innovative Future (YSRM 2019 and REIF 2019) (USB Flash Drive), 6 Pages, 2019/12
In the excavation of a repository for high-level radioactive waste (HLW) disposal, it is important to understand the hydro-mechanical characteristics of the Excavation Damaged Zone (EDZ) induced around the gallery because EDZ can lead to the migration pathway of radionuclides. Thus, we performed the resin injection experiment at the 350 m gallery of Horonobe Underground Research Laboratory in Japan to investigate the characteristics of fractures induced around the gallery wall in excavation. In the experiment, we developed a low viscosity resin mixed with a fluorescent substance and injected to the borehole drilled about 1 m in length. After the experiment, we overcored around the injection borehole. The observation on the cut surface of the overcore under ultraviolet light revealed that the fractures were distributed within 0.8 m from the gallery wall. Fractures are interconnected each other in particular within 0.25 m from the niche wall. Furthermore, fractures with large aperture (about 1.0 mm) were developed in that region. These observed results will be fundamental information for understanding of the fracturing process in the EDZ.
Aoyagi, Kazuhei; Chen, Y.*; Sakurai, Akitaka; Ishii, Eiichi; Ishida, Tsuyoshi*
JAEA-Research 2017-014, 49 Pages, 2018/01
JAEA-Research-2017-014.pdf:16.29MB
In this research, we performed the resin injection experiment at the 350 m gallery of the Horonobe Underground Research Laboratory in order to identify the three dimensional distribution of fractures induced around the gallery owing to excavation. To this end, the low viscosity resin mixed with a fluorescent substance was developed and applied to the in situ resin injection experiment. As a result, the resin was successfully penetrated into the fractures around the gallery without disturbing their situation and then fixed within them. After the experiment, the rock cores around the injection borehole were drilled for the observation. The observation under ultraviolet light revealed that the extent of the development of fractures was about 0.9 m into the borehole wall. In addition, the aperture of the fractures distributed within 0.3 m from the gallery wall was ranged 1 to 2 mm, and that distributed from 0.3 to 0.9 m was less than 1 mm. On the other hand, in the borehole televiewer (BTV) survey, only one fracture within 0.2 m from the wall could be detected owing to the resolution of the survey system. Thus, it is expected that the BTV survey underestimate the extent of the development of fractures.
Hidaka, Akihide; Nakano, Yoshihiro; Watanabe, Yoko; Arai, Nobuyoshi; Sawada, Makoto; Kanaizuka, Seiichi*; Katogi, Aki; Shimada, Mayuka*; Ishikawa, Tomomi*; Ebine, Masako*; et al.
JAEA-Review 2016-011, 208 Pages, 2016/07
JAEA-Review-2016-011-01.pdf:33.85MBJAEA-Review-2016-011-02.pdf:27.68MB
JAEA has been conducting the Instructor Training Program (ITP) since 1996 under the auspices of MEXT to contribute to human resource development in currently 11 Asian countries in the field of radiation utilization for seeking peaceful use of nuclear energy. ITP consists of Instructor Training Course (ITC), Follow-up Training Course (FTC) and Nuclear Technology Seminars. In the ITP, trainings or seminars relating to technology for nuclear utilization are held in Japan by inviting nuclear related people from Asian countries to Japan and after that, the past trainees are supported during FTC by dispatching Japanese specialists to Asian countries. News Letter is also prepared to provide the broad range of information obtained through the trainings for local people near NPPs in Japan. The present report describes the activities of FY2014 ITP and future challenges for improving ITP more effectively.
Harada, Kosaku*; Nonaka, Tetsuo*; Hamada, Nobuyuki*; Funayama, Tomoo; Sakurai, Hideyuki*; Sakashita, Tetsuya; Wada, Seiichi*; Kawamura, Hidemasa*; Hasegawa, Masatoshi*; Kobayashi, Yasuhiko; et al.
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 102, 2007/02
Kato, Shoichi; Sakurai, Tadashi*; Yoshida, Eiichi
JNC TN9400 2003-107, 127 Pages, 2004/02
JNC-TN9400-2003-107.pdf:29.28MB
An oxide dispersion strengthened(ODS) ferritic steel have excellent resistance to swelling and superior creep strength, they are expected to be used as a long-life cladding material in future advallced fast reactor. In this study, sodium environmental effect on the ODS steel developed by JNC were clarified through tensile test after sodium exposure for maximum 10,000hrs and creep-rupture test in sodium at elevated temperature. The exposure to sodium was conducted using a sodium test loop constituted by austenitic steels. For the conditions of sodium exposure test, the sodium temperatures were 923K and 973K, the oxygen concentration in sodium was below 2ppm and sodium flow rate on the surface of specimen was less than 1
10 sup-4 m/s. Further the specimen with the nickel diffused was prepared, which is simulate to nickel diffusing through sodium from the surface of structural stainless steels. The main results obtained were as follows;(1)The results showed excellent sodium-resistance up to a high temperature of about 973K in stagnant sodium conditions, and its considered that the effects of sodium environment on tensile properties were negligible. In case of stagnant sodium condition, creep-rupture strength in sodium was equal to the in argon gas, and no sodium environmental effect was observed. The same is true for the creep-rupture ductility. (2)The tensile properties of nickel diffused test specimens at high temperatures simulating microstructure change were equal to that of the thermal aging process specimens. These tensile tests suggest that sodium environmental effects can be ignored. However, the effect of nickel diffusion on creep strength are not clear at present and experimental investigation are being conducted. (3)The coefficient of nickel diffusion in the ODS steel can be estimated based on the results of nickel concentration measurement. This value is larger than that of the diffusion coefficient for typical alpha-Fe steel at temperature below 973
Tamai, Hiroshi; Matsukawa, Makoto; Kurita, Genichi; Hayashi, Nobuhiko; Urata, Kazuhiro*; Miura, Yushi; Kizu, Kaname; Tsuchiya, Katsuhiko; Morioka, Atsuhiko; Kudo, Yusuke; et al.
Plasma Science and Technology, 6(1), p.2141 - 2150, 2004/02
Times Cited Count：2 Percentile：6.49(Physics, Fluids & Plasmas)The dominant issue for the the modification program of JT-60 (JT-60SC) is to demonstrate the steady state reactor relevant plasma operation. Physics design on plasma parameters, operation scenarios, and the plasma control method are investigated for the achievement of high-
. Engineering design and the R&D on the superconducting magnet coils, radiation shield, and vacuum vessel are performed. Recent progress in such physics and technology developments is presented.
; Yoshida, Eiichi; Sakurai, Tadashi*; Yaguchi, Katsumi*
JNC TN9450 2003-001, 192 Pages, 2003/03
JNC-TN9450-2003-001.pdf:11.59MB
In order to evaluation of high temperature creep strength, creep tests under internal pressure on the fuel cladding tube for fast breeder reactor (FBR) has been preformed in New Technology Development Group. In this report, the result of the creep and creep-rupture properties on the advance austenitic stainless and high-Ni steels obtained up to this time was collected. Valuable test data totals 149 points including sodium environment test data. These data will be reflected in development and design for fuel cladding material. Contents of the data sheet are as follows ; (1)Material and number of data: 15Cr-20Ni steel (2 heats) 72 points, PNC1520 steel (1 heats) 6 points, 14Cr-25Ni steel (8 heats) 56 points, High-Ni steel (1 heat) 15 points (2)Test environment : In-air, In-argon gas and In-sodium (3)Test temperature : 600
C to 750C(873K to 1023K)
Yoshida, Eiichi; Sakurai, Tadashi*; Shibahara, Itaru
JNC TN9400 2003-050, 77 Pages, 2003/03
JNC-TN9400-2003-050.pdf:5.93MB
Sodium-bond double porous-plug is one of the candidates in development of the long-life life control rod for prototype reactor MONJU. Gas hold pressure and sodium penetration pressure of the porous-plug in liquid sodium are an important factor which determines the filling up of sodium into porous-plug and the gas plenum length in control rod pin. In this study, the fundamental characteristic of porous-plug was clarified by experiment in high temperature sodium. Moreover, the characteristic equation of design for a porous-plug was evaluated based on the obtained data.
Kobayashi, Katsuhei*; Iguchi, Tetsuo*; Iwasaki, Shin*; Aoyama, Takafumi*; Shimakawa, Satoshi; Ikeda, Yujiro; Odano, Naoteru; Sakurai, Kiyoshi; Shibata, Keiichi; Nakagawa, Tsuneo; et al.
JAERI 1344, 133 Pages, 2002/01
The JENDL Dosimetry File 99 (JENDL/D-99) has been prepared for determinations of neutron flux/fluence and energy spectrum at specific neutron fields. This file contains data for 67 reactions with 47 nuclides. Cross sections for 33 major dosimetry reactions and their covariance data were simultaneously generated and the other 34 reaction data were mainly adopted from the first version, JENDL/D-91. The GMA code was mainly used for most of the evaluation procedures by referring the basic experimental data in EXFOR. The resultant data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-6 format. In order to confirm reliability of the data, several integral tests have been carried out: comparison with the data in IRDF-90V2 and average cross sections measured in fission neutron fields, fast/thermal reactor spectra, DT neutron fields and Li(d,n) neutron fields. The contents of JENDL/D-99 and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form in the Appendix.
Harada, Kosaku*; Nonaka, Tetsuo*; Sakurai, Hideyuki*; Kawamura, Hidemasa*; Hasegawa, Masatoshi*; Nakano, Takashi*; Hamada, Nobuyuki*; Wada, Seiichi*; Kobayashi, Yasuhiko; Funayama, Tomoo; et al.
no journal, ,
no abstracts in English
Harada, Kosaku*; Nonaka, Tetsuo*; Hamada, Nobuyuki*; Funayama, Tomoo; Sakurai, Hideyuki*; Wada, Seiichi*; Sakashita, Tetsuya; Hasegawa, Masatoshi*; Kobayashi, Yasuhiko; Nakano, Takashi*
no journal, ,
no abstracts in English
Sakurai, Takeshi; Yabuuchi, Yukiko; Arai, Nobuyoshi; Sawada, Makoto; Yamashita, Kiyonobu; Sato, Nobuyuki; Torata, Shinichiro; Kanaizuka, Seiichi; Nakamura, Kazuyuki
no journal, ,
Outline of the Instructor Training Program, which is contracted with MEXT, for ten countries in Asia, and status of the Follow-up Training Course, which is one of the three major courses and conducted in Asian countries, will be reported.
Sakurai, Eiko*; Sakurai, Eiichi*; Ishii, Keizo*; Yamauchi, Shosei*; Koshio, Shigeki*; Koka, Masashi; Sato, Takahiro; Kamiya, Tomihiro
no journal, ,
no abstracts in English
Nakamura, Kazuyuki; Arai, Nobuyoshi; Kanaizuka, Seiichi; Sakurai, Takeshi; Sawai, Tomotsugu; Sawada, Makoto; Nakagawa, Norio; Murakami, Hiroyuki; Yabuuchi, Yukiko; Yamashita, Kiyonobu; et al.
no journal, ,
JAEA is performing the human resource development for eleven Asian countries as contract with MEXT. Problems and their response to this works will be reported.
Sakurai, Eiko*; Sakurai, Eiichi*; Ishii, Keizo*; Koshio, Shigeki*; Ito, Shun*; Matsuyama, Shigeo*; Koka, Masashi; Yamada, Naoto; Kitamura, Akane; Sato, Takahiro; et al.
no journal, ,
no abstracts in English
