Impact assessment for internal overflow in JRR-3

Tokunaga, Sho; Iguchi, Shintaro; Kawamura, Sho; Hirane, Nobuhiko

JAEA-Technology 2022-004, 74 Pages, 2023/02

JAEA-Technology-2022-004.pdf:2.46MB

In JRR-3, in response to the new regulatory standard for research reactors that is enforced December 2013, we submitted the application document of reactor installation license for the JRR-3 on September 2014, and acquired the permission on November 2018. Thereafter, we carried out impact assessment for internal overflow based on the design principles as described in the application document of reactor installation license for the JRR-3. There are two legal requirements for internal overflow. The first is to ensure that the necessary safety functions are not lost due to internal overflow that occur in the facility. The second is to prevent leakage of liquid containing radioactive materials outside the radiation controlled area in the event of an internal overflow. For these requirements, assuming each overflow source, it was confirmed that the necessary safety functions would not be lost and that liquid containing radioactive materials would not leak outside the controlled area. Regarding these assessments, design and construction plans were submitted in installments, and the approvals were obtained sequentially. This report shows the result that is impact assessment for internal overflow in JRR-3.

Seismic evaluation of the CRDM and the CRDM guide tube for JRR-3

Kikuchi, Masanobu; Kawamura, Sho; Hosoya, Toshiaki

JAEA-Technology 2021-040, 86 Pages, 2023/02

JAEA-Technology-2021-040.pdf:3.26MB

In JRR-3, in response to new regulatory standard for research and test reactor which is enforced December 2013, we established new design basis ground motion for confirming new regulatory standard and carried out seismic evaluations of the appointments, instruments and structures which are installed in JRR-3 by using that earthquake motion. This report shows that the result of evaluations by fatigue strength evaluation, which is more detailed evaluation approach, about Control Rod Drive Mechanism (CRDM) and the CRDM Guide Tube that have gotten the serious result of seismic safety margin by using time history response analysis method. As a result, it was confirmed that CRDM and the CRDM Guide Tube have sufficient seismic safety margin.

Neutron scattering study of spin fluctuations in LaSrCuO by four-dimensional mapping of neutron cross-sections using the 4SEASONS chopper spectrometer

Wakimoto, Shuichi; Ikeuchi, Kazuhiko*; Arai, Masatoshi; Fujita, Masaki*; Kajimoto, Ryoichi; Kawamura, Sho*; Matsuura, Masato*; Nakajima, Kenji; Yamada, Kazuyoshi*

JPS Conference Proceedings (Internet), 8, p.034013_1 - 034013_6, 2015/09

https://doi.org/10.7566/JPSCP.8.034013

Beam commissioning of the J-PARC linac DTL1 at KEK

Kondo, Yasuhiro; Akikawa, Hisashi; Anami, Shozo*; Asano, Hiroyuki*; Fukui, Yuji*; Igarashi, Zenei*; Ikegami, Kiyoshi*; Ikegami, Masanori*; Ito, Takashi; Kawamura, Masato*; et al.

Proceedings of 1st Annual Meeting of Particle Accelerator Society of Japan and 29th Linear Accelerator Meeting in Japan, p.156 - 158, 2004/08

A commissioning of the J-PARC linac DTL1 is now under way at KEK. A 30mA H beam was accelerated to 19.7-MeV, and 100% transmission was obtained with a 20-msec-pulse-width and 12.5-Hz-repetition beam. In this paper, present status of the DTL1 commissioning and preliminary results of the commissioning, such as emittance measurements, are presented.

Current status of JRR-3, 1; Outline and recovery works after the Great East Japan Earthquake

Kawamura, Sho; Wada, Shigeru; Murayama, Yoji

no journal, , 

JRR-3 (Japan Research Reactor No.3) at Tokai site of JAEA is a light water cooled and moderated swimming pool type research reactor with nominal thermal power of 20 MW. JRR-3 is utilized from academic research to industrial use as neutron beam experiments, irradiation tests of the reactor material, and manufacturing radio isotopes for medicine use and the silicon semiconductor by neutron transmutation doping (NTD). Reactor reached first critical state in 1990 and it was continued operating for 20 years till the Great East Japan Earthquake on 2011. JRR-3 was in this regular maintenance period, when the Great East Japan Earthquake took place on 11th March 2011. The Great East Earthquake's acceleration was measured larger seismic acceleration than that of seismic design of JRR-3. The ground around rhe buildings was sunk about 40 cm. Therefore, some facilities were damaged such as exhaust duct led to a stack and electric transformers in secondary cooling tower. However, the reactor building with the solid foundations and the safety-related facilities survived the earthquake without serious damage, and no radioactive leakage has been occurred. To confirm soundness, checking and testing of the integrity for every components of JRR-3 have been carried out without delay.

Status of JRR-3 corresponding to new regulatory standards, 2; Protection from external events

Suzuki, Makoto; Kawamura, Sho; Kobayashi, Tetsuya; Horiguchi, Hironori; Wada, Shigeru

no journal, , 

no abstracts in English

Seismic evaluation of control rod for JRR-3

Kikuchi, Masanobu; Kawamura, Sho; Araki, Masaaki

no journal, , 

We carried out seismic evaluation and showed suitability in the new regulatory standard of JRR-3. CRDM and insertion property of control rod carried out more detailed approach because the past results had gotten the serious results of seismic safety margin. As a result, it was confirmed that CRDM and insertion property of control rod have sufficient seismic safety margin.