Development of a probabilistic risk assessment method for combined hazards; A Classification and modeling framework for multihazard events

Choi, B.; Nishida, Akemi; Tsutsumi, Hideaki*; Takada, Tsuyoshi

Proceedings of Probabilistic Safety Assessment and Management & Asian Symposium on Risk Assessment and Management (PSAM17 & ASRAM2024) (Internet), 8 Pages, 2024/10

The Fukushima Daiichi Nuclear Power Plant accident highlighted the importance of developing safety assessment methods that consider multihazard events involving numerous simultaneously occurring events such as earthquakes (shaking) and tsunamis (submersion). When addressing such multihazard events, traditional methods often focus on assessing the load combinations of general structures in their structural designs and adopt simple selection criteria. However, these methods fall short when evaluating, countering, and screening external events, such as earthquakes, tsunamis, strong winds, and concentrated heavy rainfall, that occur simultaneously or in a chain. To address this, we reviewed existing literature on multihazard assessment methods, focusing particularly on scenarios involving earthquake and tsunami events. Based on concepts and basic theories, we examined various methods for addressing multihazard scenarios and classified their characteristics. Specifically, several multihazard scenarios were surveyed, and the relationships between multiple hazards were organized. In addition, common causes leading to combined events, their mutual influences, and potential cascading effects were analyzed.

Comparative study on equipment damage correlation during earthquakes using a three-dimensional detailed and a sway-rocking analysis models for nuclear reactor building

Choi, B.; Nishida, Akemi; Takito, Kiyotaka; Tsutsumi, Hideaki*; Takada, Tsuyoshi

Proceedings of 30th International Conference on Nuclear Engineering (ICONE30) (Internet), 8 Pages, 2023/05

no abstracts in English

User's manual of a computer code for evaluating effectiveness of seismic component base isolation, EBISA; Function of dynamic response analysis code

Tsutsumi, Hideaki*; Sugino, Hideharu*; Onizawa, Kunio; Mori, Kazunari*; Yamada, Hiroyuki*; Shibata, Katsuyuki; Ebisawa, Katsumi*

JAEA-Data/Code 2006-004, 167 Pages, 2006/03

JAEA-Data-Code-2006-004.pdf:6.41MB

EBISA (Equipment Base Isolation System Analysis) code evaluates the effectiveness of seismic isolation for the important components in the seismic safety, and consists of the three codes, probabilistic seismic hazard code (SHEAT), seismic dynamic response analysis code (RESP) and seismic failure probability and frequency evaluation code. In these codes, RESP code is used for the calculation of the dynamic response behavior of a nuclear component with seismic isolation devices. This report describes the overall explanation of EBISA, and user's guide of RESP code including the analysis function, input manual and sample problem.

Study on structural integrity evaluation of core shroud based on crack growth analysis (Contract research)

Onizawa, Kunio; Tsutsumi, Hideaki*; Suzuki, Masahide; Shibata, Katsuyuki; Ueno, Fumiyoshi; Kaji, Yoshiyuki; Tsukada, Takashi; Nakajima, Hajime*

JAERI-Tech 2003-073, 125 Pages, 2003/08

JAERI-Tech-2003-073.pdf:11.62MB

Concerning the cracks due to stress corrosion cracking (SCC) observed on the core shrouds of BWRs, a study was conducted on structural integrity evaluation based on crack growth analysis. The cracks investigated were those observed on the regions of lower ring and support ring of the core shroud at Kashiwazaki-Kariwa Nuclear Power Station (NPS) Unit-3, and that on the middle shell region of the core shroud at Fukushima Daiichi NPS Unit-4 of Tokyo Electric Power Company. It was confirmed through data analysis of past SCC growth rate experiments applicable to the condition of the ring regions that the SCC growth rate prescribed in the JSME rule was conservative. The analysis on the core shroud rigidity with a crack indicated that the rigidity reduction was small enough not to affect the dynamic seismic response for the regions studied. Through the comparison of the required area in a cracked section or the allowable crack length, and crack growth analysis results, it was confirmed that the integrity of the core shrouds would be maintained even 4 effective full power years later.

Study on the dynamic response analysis for evaluating the effectiveness of base isolation for nuclear components

Mori, Kazunari*; Tsutsumi, Hideaki*; Yamada, Hiroyuki; Ebisawa, Katsumi; Shibata, Katsuyuki

JAERI-Tech 2001-037, 85 Pages, 2001/06

JAERI-Tech-2001-037.pdf:6.27MB

no abstracts in English

Earthquake observation database in JAERI Oarai site obtained by vertical instrument arrays from 1987-2000

Ebisawa, Katsumi; Yamada, Hiroyuki; Tsutsumi, Hideaki*; Shibata, Katsuyuki; Ando, Kazuhiro*; Baba, Osamu; Suzuki, Hideyuki

JAERI-Data/Code 2001-009, 96 Pages, 2001/03

JAERI-Data-Code-2001-009.pdf:4.14MB

no abstracts in English

Dynamic behavior and base isolation effect of three dimensional base isolation test system for nuclear components

Tsutsumi, Hideaki*; Yamada, Hiroyuki; Ebisawa, Katsumi; Shibata, Katsuyuki; Fujimoto, Shigeru*

Doboku Gakkai Dai-2-Kai Menshin, Seishin Korokiumu Koen Rombunshu, p.75 - 82, 2000/11

no abstracts in English

Dynamic response of base isolation test system for nuclear components under natural seismic motion

Tsutsumi, Hideaki*; Yamada, Hiroyuki; Teragaki, Toshio*; Ebisawa, Katsumi; Shibata, Katsuyuki

Seismic Engineering 2000 (PVP-Vol.402-1), p.141 - 146, 2000/00

no abstracts in English

Development of seismic response analysis model of nuclear facility based on strong motion records and 4SID

Kato, Rino*; Hida, Takenori*; Tsutsumi, Hideaki*; Takada, Tsuyoshi

no journal, , 

With the aim of constructing a more realistic earthquake response analysis model of a nuclear facility, we constructed a model using the system identification method developed by the authors making maximum use of the strong motion observation records in the past earthquakes, and discussed its validity.

Probabilistic observation of design basis ground motions of NPPS

Takada, Tsuyoshi; Tsutsumi, Hideaki*; Kawata, Manabu

no journal, , 

The 2006 seismic design review guide requires results of their site-specific probabilistic seismic hazard assessment (PSHA) for setting Design Basis Ground Motions (DBGMs) to verify seismic safety of Nuclear Power Plants (NPPs). All electric utilities have submitted their results of their DBGMs to the NRA (Nuclear Regulatory Authority) together with the results of their PSHA. The AEPs (Annual Exceedance Probabilities) of DBGMs reflect not only the site-specific physical earthquake environment but also degree of design conservatisms which each electric utility wants to maintain for their NPPs. The present paper, based on the publicly available documents submitted to NRA, demonstrates the AEPs of the DBGMs of 16 NPPs in Japan and shows the regulatory requirements as well as utilities' decision by statistically analyzing the AEPs, which certainly can lead to risk-informed decision-making activities for nuclear safety assurance in Japan.