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.

Presentations at international safeguards sessions in the 21st annual meeting; symposium on safeguards and nuclear material management

Nishimura, Hideo

Kaku Busshitsu Kanri Senta Nyusu, 28(8), p.5 - 7, 1999/08

no abstracts in English

Buckling evaluation method of Mod. 9Cr-1Mo steel cylinder under horizontal and vertical loads, 1; Effects of material properties and initial imperfection

Miura, Kazuhiro*; Okafuji, Takashi*; Sago, Hiromi*; Shimomura, Kenta; Okajima, Satoshi; Sato, Kenichiro*

no journal, , 

Buckling evaluation methods capable of evaluating elasto-plastic buckling under axial compression, bending, and shear loads are required for cylindrical vessels of fast reactors in order to cope with thinning due to the increase in diameter, adoption of new materials, and adoption of seismic isolation design due to the increase in the standard seismic ground motion. Buckling evaluation methods corresponding to the above are being considered in the fast reactor standards of the Japan Society of Mechanical Engineers. In this study, in order to examine the applicability of the proposed buckling evaluation equation, Monte Carlo simulation was carried out using material properties and initial imperfections, which are the fluctuation factors of buckling strength, as parameters, and the effect of the fluctuation of these factors on buckling load was evaluated. When the buckling load was normalized by the buckling critical value according to the proposed formula using the longitudinal elastic modulus and the design yield stress of JSME S NC2-2013, the 95% lower confidence limit exceeded the threshold of the proposed formula for both the vertical single load condition and the horizontal and vertical combined load condition. The results show that the buckling critical value calculated by using the design yield stress in the proposed equation is more conservative than the 95% lower confidence limit of the actual buckling load affected by the scatter of material properties and others.