Improve long periodic ground motion evaluation with the epicenter on the border between Fukushima and Ibaraki prefectures in seismic design of nuclear facilities

Kirita, Fumio; Tominaga, Masahiro; Yamazaki, Toshihiko; Seshimo, Kazuyoshi; Uryu, Mitsuru

JAEA-Research 2022-006, 61 Pages, 2023/02

JAEA-Research-2022-006.pdf:6.24MB

Nuclear Fuel Cycle Engineering Laboratories (NCL) has been observing ground motion for a long time. On the border from northern Ibaraki prefecture to Fukushima prefecture, inland crustal earthquakes occur less frequently until the 2011 off the Pacific coast of Tohoku Earthquake (hereinafter referred to as Tohoku Earthquake). After Tohoku Earthquake, aftershocks have become more frequent in this area, and in the Hamadori region of Fukushima earthquake that a remarkable long periodic component was observed in the NCL seismic observation record. Until now there were no such things that long periodic components were observed at the observation points near the epicenter of April 2011 Fukushima earthquake, but it was thought basin structure in deep basement around the NCL affected the propagation process to NCL by reflection survey result. As basement structure of NCL affected the seismic wave propagation process, the seismic wave repeatedly reflects and refracts. For that reason, long periodic components of seismic waves may be possibly amplified. In this study, in order to refine the long periodic ground motion evaluation, using a three dimensional ground structure model (3D model) that can reflect the shape of the deep basement structure around the NCL. When modeling 3D ground structure which has a width of about 80km and a length of about 110km and ranges from the epicenter area of April 2011 Fukushima earthquake to the northern coastal area of Ibaraki prefecture modeled, improved the optimum ground structure model using multiple observation records and performed simulation analysis.

Gamma-ray imaging using three-dimensional shadow images created by coded solid

Kitayama, Yoshiharu; Nogami, Mitsuhiro*; Hitomi, Keitaro*

KEK Proceedings 2022-3, p.46 - 53, 2023/01

The position of a streetlight can be predicted from the direction and shape of one's shadow projected on the street at night by the light of the streetlight. The application of this idea to gamma-ray imagers is known as coded aperture. In this study, we proposed the Coded Cube Camera - POrtable (C3PO), which has a three-dimensional shielding and scintillator crystal arrangement, and is composed of lead, scintillator, and depletion cubes randomly arranged in a 333 Rurik's cube shape, with each. The output of each scintillator produces a three-dimensional shadow pattern, which is returned to the source direction distribution by unfolding. In this study, we investigated the characteristics and feasibility of the system by simulation using Geant 4.

Update on the regional-scale 3D geological model in the Horonobe Underground Research Laboratory Project

Sakai, Toshihiro; Ishii, Eiichi

JAEA-Data/Code 2021-009, 13 Pages, 2021/08

JAEA-Data-Code-2021-009.pdf:1.9MB
JAEA-Data-Code-2021-009-appendix(CD-ROM).zip:42.79MB

Japan Atomic Energy Agency is performing the Horonobe Underground Research Laboratory Project, which includes a scientific study of the deep geological environment as a basis of research and development for the geological disposal of high level radioactive wastes, in order to establish comprehensive techniques for the investigation, analysis and assessment of the deep geological environment in the sedimentary rock. The numerical data of 3D geological model in regional-scale was compiled in 2019 as JAEA-Data/Code 2019-007, and then this report updates a part of the numerical data of 3D geological model around the underground facilities.

Three-dimensional analysis using polygons in Particle and Heavy Ion Transport code System (PHITS)

Furuta, Takuya

ANS RPSD 2018; 20th Topical Meeting of the Radiation Protection and Shielding Division of ANS (CD-ROM), 5 Pages, 2018/08

Recently we introduced a function in PHITS to treat tetrahedral-mesh geometry. Tetrahedral-mesh geometry is a structure composed of combination of tetrahedrons and able to construct complex objects. Tetrahedral-mesh objects can be obtained by converting polygon data using mesh generation software such as TetGen. We also implemented a function in PHITS to export tally results into the format of the three-dimensional visualization software ParaView. TetGen is able to convert the polygon data into ParaView format. Together with these tools, three-dimensional analysis can be realized for PHITS simulation using a polygon objects.

Applicability of the three-dimensional laser scanning to the fracture mapping on a gallery wall

Hayano, Akira; Itakura, Kenichi*

Journal of MMIJ, 133(4), p.76 - 86, 2017/04

https://doi.org/10.2473/journalofmmij.133.76

no abstracts in English

Design of the anchor wall using 3D finite element method

Iha, Akane*; Matsubara, Hitoshi; Iraha, Shigeo*; Kanda, Yasuyuki*

Konkurito Kogaku Nenji Rombunshu (DVD-ROM), 27(2), p.1663 - 1668, 2005/00

The concrete structures such a reactor building are able to resist external forces by interaction behavior such as concrete, reinforcements, steel frames and the foundation. Therefore, it is a very important subject to solve analytically the displacement behavior and the stress distribution because the safety of structures and safe security can be offered by it. In general, such a problem is solved by using the beam theory. However, it is impossible to evaluate the different behavior or stress distribution on every component. In this paper, 3-dimensional finite element analysis of full-scale anchor wall is performed. In addition, all composition material is taken into consideration in this analysis. Consequently, concrete interaction behavior with many components is solved, and the displacement behavior and concentration of stress also is elucidated.

Theoretical background and user's manual for the computer code on groundwater flow and radionuclide transport calculation in porous rock

*;

JNC TN8400 2001-027, 131 Pages, 2001/11

JNC-TN8400-2001-027.pdf:0.8MB

In order to document a basic manual about input data, output data, execution of computer code on groundwater flow and radionuclide transport calculation in heterogeneous porous rock, we investigated the theoretical background about geostastical computer codes and the user's manual for the computer code on groundwater flow and radionuclide transport which calculates water flow in three dimension, the path of moving radionuclide, and one dimensional radionuclide migration. In this report, based on above investigation we describe the geostastical background about simulating heterogeneous permeability field. And we describe construction of files, input and output data, a example of calculating of the programs which simulates heterogeneous permeability field, and calculates groundwater flow and radionuclide transport. Therefore, we can document a manual by investigating the theoretical background about geostastical computer codes and the user's manual for the computer code on groundwater flow and radionuclide transport calculation. And we can model heterogeneous porous rock and analyze groundwater flow and radionuclide transport by utilizing the information from this report.

Silicon cluster formation by molecular ion irradiation; Relationship between iradiated ion species and cluster yield

Yamamoto, Hiroyuki; Saito, Takeru; Asaoka, Hidehito

Applied Surface Science, 178(1-4), p.127 - 133, 2001/07

https://doi.org/10.1016/S0169-4332(01)00250-1

no abstracts in English

Si cluster emission by molecular ion irradiation

Yamamoto, Hiroyuki

Hoshasen Kagaku, 2001(71), p.17 - 21, 2001/03

http://ci.nii.ac.jp/naid/10010163360

no abstracts in English

Analyse on the BFS critical experiments; An analysis on the BFS-62-1 assembly

Sugino, Kazuteru; Iwai, Takehiko*;

JNC TN9400 2000-098, 182 Pages, 2000/07

JNC-TN9400-2000-098.pdf:5.74MB

In order to support the Russian excess weapons plutonium disposition, the international collaboration has been started between Japan Nuclear Cycle Development Institute (JNC) and Russian Institute of Physics and Power Engineering (IPPE). In the frame of the collaboration, JNC has carried out analyses on the BFS-62 assemblies that are constructed in the fast reactor critical experimental facility BFS-2 of IPPE. This report summarizes an experimental analysis on the BFS-62-1 assembly, which is the first core of the BFS-62 series. The core contains the enriched U0 fuel surrounded by the U0 blanket. The standard analytical method for fast reactors has been applied, which was used for the JUPITER and other experimental analyses. Due to the lack of the analytical data the 2D RZ core calculation was mainly used. The 3D XYZ core calculation was applied only for the preliminary evaluation. Further in terms of the utilization of the BFS experimental analysis data for the standard data base for FBR core design, consistency evaluation with JUPITER experimental analysis data has been performed using the cross-section adjustment method. As the result of analyses, good agreement was obtained between calculations and experiments for the criticality and the reaction rate ratio. However, it was found that accurate evaluation of the reaction rate distribution was impossible without exact consideration of the arrangement of the two types of sodium (with and without hydrogen impurity), which can be accommodated by the 3D core analysis, thus it was essentia1. In addition, it was clarifie that there was a room for an improvement of the result on the reaction rate distribution in the blanket and shielding regions. The application of the 3D core calculation improved the result on the control rod worth because 3D core model can more exactly consider the shape of the control rod. Furthermore it was judged that the result of the analysis on the sodium void reactivity .....