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Oda, Chie; Kawama, Daisuke*; Shimizu, Hiroyuki*; Benbow, S. J.*; Hirano, Fumio; Takayama, Yusuke; Takase, Hiroyasu*; Mihara, Morihiro; Honda, Akira
Journal of Advanced Concrete Technology, 19(10), p.1075 - 1087, 2021/10
Times Cited Count:0 Percentile:0(Construction & Building Technology)Concrete in a transuranic (TRU) waste repository is considered a suitable material to ensure safety, provide structural integrity and retard radionuclide migration after the waste containers fail. In the current study, coupling between chemical, mass-transport and mechanical, so-called non-linear processes that control concrete degradation and crack development were investigated by coupled numerical models. Application of such coupled numerical models allows identification of the dominant non-linear processes that will control long-term concrete degradation and crack development in a TRU waste repository.
Benbow, S. J.*; Kawama, Daisuke*; Takase, Hiroyasu*; Shimizu, Hiroyuki*; Oda, Chie; Hirano, Fumio; Takayama, Yusuke; Mihara, Morihiro; Honda, Akira
Crystals (Internet), 10(9), p.767_1 - 767_33, 2020/09
Times Cited Count:2 Percentile:26.57(Crystallography)Details are presented of the development of a coupled modeling simulator for assessing the evolution in the near-field of a geological repository for radioactive waste disposal where concrete is used as a backfill. The simulator uses OpenMI, a standard for exchanging data between simulation software programs at run-time, to form a coupled chemical-mechanical-hydrogeological model of the system. The approach combines a tunnel scale stress analysis finite element model, a discrete element model for accurately modeling the patterns of emerging cracks in the concrete, and a finite element and finite volume model of the chemical processes and alteration in the porous matrix and cracks in the concrete, to produce a fully coupled model of the system. Combining existing detailed simulation software in this way with OpenMI has the benefit of not relying on simplifications that might be necessary to combine all of the modeled processes in a single piece of software.
Sekio, Yoshihiro; Yoshimochi, Hiroshi; Kosaka, Ichiro; Hirano, Hiroyasu; Koyama, Tomozo; Kawamura, Hiroshi
Proceedings of 52nd Annual Meeting of Hot Laboratories and Remote Handling Working Group (HOTLAB 2015) (Internet), 8 Pages, 2015/09
Due to the Fukushima Daiichi Nuclear Power Plant accident in March 2011, the safe and secure implementations of the decommissioning for Fukushima Daiichi Nuclear Power Plant has been positioned as the urgent tasks in Japan. Japan Atomic Energy Agency has a critical mission of analysing radioactive wastes having generated by the accident for long-term storage and disposal methods. This will be performed in two hot laboratories to be constructed in Okuma Analysis and Research Center at Fukushima Daiichi Nuclear Power Plant site. In one laboratory, radioactive wastes such as rubbles and secondary wastes will be treated, whereas debris such as fuel debris and high dose structural materials will be handled in the other laboratory. The detail considerations for advanced techniques and experimental apparatus to be installed are underway.
Higuchi, Hidetoshi; Koizumi, Kenji; Hirano, Hiroyasu; Tasaka, Masayuki*; Washiya, Tadahiro; Kobayashi, Tsuguyuki*
Journal of Power and Energy Systems (Internet), 4(1), p.244 - 251, 2010/04
no abstracts in English
Kitagaki, Toru; Tasaka, Masayuki; Higuchi, Hidetoshi; Koizumi, Kenji; Hirano, Hiroyasu; Washiya, Tadahiro; Kobayashi, Tsuguyuki*
Proceedings of 17th International Conference on Nuclear Engineering (ICONE-17) (CD-ROM), 5 Pages, 2009/06
JAEA has been developing a reliable disassembly system for FBR fuel reprocessing as a part of Fast Reactor Cycle Technology Development (FaCT). We fabricated the disassembly system testing machine. In this paper, we described design of it.
Hirano, Hiroyasu
Saikuru Kiko Giho, (23), 0 Pages, 2004/00
Focusing on the cover layer materials (as the Radon Barrier Materials), which could have the effect to restrain the radon from scattering into the air and the effect of the radiation shielding, we produced the radon barrier materials with crude bentonite on an experimental basis, using the rotary type comprehensive unit for grinding and mixing, through which we carried out the evaluation of the characteristics thereof.
; Hirano, Hiroyasu; Koyama, Tomozo
OECD/NEA 7th information exchange meeting, 0 Pages, 2002/00
None
; Hirano, Hiroyasu; ; Tanaka, Yasumasa; Kawata, Tomio
International Conference on Envilonmental of Fuel, ,
None
Hirano, Hiroyasu; ; ; Nomura, Kazunori; ;
International Information Exchange Programe on Actinide & Fission Product Separation & Transmutation, ,
None
Hirano, Hiroyasu; Nomura, Kazunori; ; ; ;
International Information Exchange Programe on Actinide & Fission Product Separation & Transmutation, ,
None
Higuchi, Hidetoshi; Toya, Yuichi*; Washiya, Tadahiro; Koizumi, Kenji; Hirano, Hiroyasu
no journal, ,
Japan Atomic Energy Agency (JAEA) has been developing a reliable disassembly system for FBR fuel reprocessing as a part of FaCT. As For the disassembly system, laser type disassembly system had been developed, but it had some subjects as adhesion and fuel pin damage caused by dross. Then JAEA have proposed a new disassembly technology by mechanical disassembly system that consists of a mechanical cutting step and a wrapper tube pulling step. Mechanical cutting performance and pulling separation performance are confirmed by fundamental test, and Fundamental design of the mechanical disassembly system is established.
Goto, Ichiro; Watanabe, So; Koizumi, Kenji; Hirano, Hiroyasu; Sano, Yuichi; Koma, Yoshikazu
no journal, ,
no abstracts in English
Higuchi, Hidetoshi; Koizumi, Kenji; Hirano, Hiroyasu; Washiya, Tadahiro
no journal, ,
no abstracts in English
Higuchi, Hidetoshi; Koizumi, Kenji; Hirano, Hiroyasu; Tasaka, Masayuki; Washiya, Tadahiro; Kobayashi, Tsuguyuki*
no journal, ,
From previous reports, the powdered fuel was considered to be suitable for the preparation of high concentrated solution efficiently. And the short stroke shearing technology is expected to make the powdered fuel rationally. In this study, the short stroke shearing tests with simulated fuel pin bundle has been carried out at engineering scale. From these tests, fundamental data of the short stroke shearing characteristics were obtained.
Fukushima, Mineo; Nagai, Takayuki; Kikuchi, Kotaro*; Hirano, Hiroyasu; Myochin, Munetaka
no journal, ,
Measurement techniques for density and liquid level of molten salt are very important elements in material accountancy system for pyro-processing and also in process control system. Test equipments were developed for the in-situ measurement of density and liquid level of molten salt and provided to the measurement experiments. Measurement of the density of LiCl-KCl eutectic showed a good agreement with published data in an error of 0.2%. Measurement of the liquid level of LiCl-KCl eutectic showed an error of 0.5 mm against theoretical values. From these results, both techniques were considered to be promising although the additional data accumulation is needed to estimate the performance statistically by using practical equipment.
Higuchi, Hidetoshi; Koizumi, Kenji; Hirano, Hiroyasu; Kitagaki, Toru; Washiya, Tadahiro; Kobayashi, Tsuguyuki*; Tasaka, Masayuki*
no journal, ,
no abstracts in English
Kitagaki, Toru; Higuchi, Hidetoshi; Koizumi, Kenji; Hirano, Hiroyasu; Tasaka, Masayuki*; Washiya, Tadahiro; Kobayashi, Tsuguyuki*
no journal, ,
no abstracts in English
Nagai, Takayuki; Kikuchi, Kotaro*; Hirano, Hiroyasu; Fukasawa, Kazuhito*; Uehara, Akihiro*; Yamana, Hajimu*
no journal, ,
In the dry reprocessing process for spent nuclear fuel by the electro-metallurgical method, we are studying the online monitoring technique of dissolved ion concentration in molten LiCl-KCl eutectic. In this study, the cyclic voltammetry was carried out in the molten LiCl-KCl eutectic added lanthanide chlorides (NdCl, etc.) and we confirmed that the peak current density by the reductive reaction of dissolved ions increased in proportion to the dissolved ion concentration until about 4 mol%.
Nagai, Takayuki; Kikuchi, Kotaro*; Kano, Yoshiharu*; Hirano, Hiroyasu
no journal, ,
On the dry reprocessing process study by using a molten sodium molybdate, the SUS316 stainless steel of clad material was dissolved into the melt. In this study, we carried out the immersed corrosion test of Fe, Cr, and Ni in molten sodium molybdate, and estimated the corrosion behavior of these material and dissolution content in the melt.