Proposal of simulation material test technique for clarifying the structure failure mechanisms under excessive seismic loads

Hashidate, Ryuta; Kato, Shoichi; Onizawa, Takashi; Wakai, Takashi; Kasahara, Naoto*

Proceedings of ASME 2021 Pressure Vessels and Piping Conference (PVP 2021) (Internet), 9 Pages, 2021/07

It is very essential to clarify the structure failure mechanisms under excessive seismic loads. However, structural tests using actual structural materials are very difficult and expensive. Therefore, we have proposed the structure test approach using lead alloys in order to simulate the structure failure mechanisms under the excessive seismic loads. In this study, we conducted material tests using lead alloy and verified the effectiveness of the simulated material tests. Moreover, we formulated inelastic constitutive equations (best fit fatigue curve equation and cyclic stress range - strain range relationship equation) of lead alloy based on the results of a series of material tests. Nonlinear numerical analyses, e.g. finite element analyses, can be performed using the proposed equations. A series of simulation material test technique enables structural tests and analyses using lead alloy to simulate the structure failure phenomena under excessive seismic loads.

A Proposal of inelastic constitutive equations of lead alloys used for structural tests simulating severe accident conditions

Hashidate, Ryuta; Onizawa, Takashi; Wakai, Takashi; Kasahara, Naoto*

Proceedings of 2019 ASME Pressure Vessels and Piping Conference (PVP 2019) (Internet), 10 Pages, 2019/07

Under the severe accident conditions, structural materials of nuclear power plants are subjected to excessive high temperature. Although it is very essential to clarify how the structure collapses under the severe accident conditions, the failure mechanisms in such high temperatures are not clarified. However, it is very difficult and expensive to perform structural tests using actual structural materials. Therefore, we propose to use lead alloys instead of actual structural materials. Because the strength of lead alloys is much poorer than that of the actual structural materials, failure can be observed at low temperature and by small load. For demonstration of analogy between the failure mechanisms of lead alloys structure at low temperature and those of the actual structures at high temperature, numerical analyses are required. So, we confirm the material characteristics of lead alloys and develop inelastic constitutive equations of lead alloy required for finite element analyses.

Inverse problem on indentation load and depth curve; Identification of material constants by using a spherical indenter

Futakawa, Masatoshi; Wakui, Takashi*; Naoe, Takashi*; Ioka, Ikuo

Jikken Rikigaku, 4(3), p.222 - 227, 2004/09

https://doi.org/10.11395/jjsem2001.4.222

no abstracts in English

Creep characteristics of Alloy 800H

Tachibana, Katsumi; Nishi, Hiroshi; Eto, Motokuni;

JAERI-Tech 98-010, 107 Pages, 1998/03

JAERI-Tech-98-010.pdf:3.52MB

no abstracts in English

Estimations of creep behavior and failure life for a circumferentially notched specimen

*; *; Kikuchi, Kenji

Nihon Kikai Gakkai Rombunshu, A, 63(612), p.1737 - 1743, 1997/08

https://doi.org/10.1299/kikaia.63.1737

no abstracts in English

Inelastic constitutive equation based on a new viscoelastic material model

H.J.Penkalla*; Kikuchi, Kenji

Nihon Kikai Gakkai Rombunshu, A, 62(593), p.162 - 167, 1996/01

https://doi.org/10.1299/kikaia.62.162

no abstracts in English

Recent advance in life prediction for HTGR applications

Kikuchi, Kenji; Kaji, Yoshiyuki;

Int. J. Press. Vessels Piping, 58, p.267 - 276, 1994/00

https://doi.org/10.1016/0308-0161(94)90062-0

no abstracts in English

Two-phase flow characteristics analysis code: MINCS

Watanabe, Tadashi; Hirano, Masashi; ; Tanabe, Fumiya; Kosaka, Atsuo

JAERI 1326, 232 Pages, 1992/03

JAERI-1326.pdf:4.82MB

no abstracts in English

Research on structural design criteria at very high temperature; State of the arts

Atsuryoku Gijutsu, 29(3), p.177 - 181, 1991/00

http://joi.jlc.jst.go.jp/JST.Journalarchive/hpi1972/11.177

no abstracts in English

Evaluation of interfacial shear model for bubbly flow regime with the MINCS code

Hirano, Masashi; ; ; ; *; *; *;

Proc.2nd Int.Topical Meeting on Nuclear Power Plant Thermal Hydraulics and Operations, p.1 - 80, 1986/00

no abstracts in English

Development of inelastic constitutive equations of lead alloys used for structural tests simulating severe accident conditions

Hashidate, Ryuta; Kato, Shoichi; Onizawa, Takashi; Wakai, Takashi; Kasahara, Naoto*

no journal, , 

Under the severe accident conditions, structural materials of nuclear power plants are subjected to excessive high temperature. Although it is very essential to clarify how the structure collapses under the severe accident conditions, the failure mechanisms in such high temperatures are not clarified. However, it is very difficult and expensive to perform structural tests using actual structural materials. Therefore, we propose to use lead alloys instead of actual structural materials. Because the strength of lead alloys is much poorer than that of the actual structural materials, failure can be observed at low temperature and by small load. For demonstration of analogy between the failure mechanisms of lead alloys structure at low temperature and those of the actual structures at high temperature, numerical analyses are required. So, we confirm the material characteristics of lead alloys and develop inelastic constitutive equations of lead alloy required for finite element analyses.