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Watakabe, Tomoyoshi; Yamamoto, Tomohiko; Fukasawa, Tsuyoshi*; Okamura, Shigeki*; Somaki, Takahiro*; Morobishi, Ryota*; Sakurai, Yu*; Kato, Koji*
Nihon Kikai Gakkai Rombunshu (Internet), 83(850), p.16-00444_1 - 16-00444_14, 2017/06
A seismic isolation system composed of a thick rubber bearing and an oil damper has been developed for Sodium-Cooled Fast Reactor. This paper focused on the aging properties of thick rubber bearings, such as basic mechanical properties and ultimate strength. Aging of the rubber bearings was reproduced using thermal degradation based on Arrhenius law.
Watakabe, Tomoyoshi; Yamamoto, Tomohiko; Fukasawa, Tsuyoshi*; Okamura, Shigeki*; Somaki, Takahiro*; Morobishi, Ryota*; Sakurai, Yu*; Kato, Koji*
Proceedings of 2016 ASME Pressure Vessels and Piping Conference (PVP 2016) (Internet), 8 Pages, 2016/07
A seismic isolation system composed of a thick rubber bearing and an oil damper has been developed for Sodium cooled Fast Reactor. One of the advantages of the isolation system is employing the thick rubber bearing in order to realize the longer vertical natural period of a plant, and it leads to mitigation of seismic loads to mechanical components. Rubber bearing technology has progressed based on many past studies, but test data regarding an aging effect is not enough. Also, there is no data of linear strain limit and breaking behavior for the thick rubber bearing after aging. This paper focuses on aging properties of the thick rubber bearing, such as basic mechanical properties and ultimate strength. An aging promote test of the thick rubber bearing was performed by using 1/2 scale and 1/8 scale rubber bearings. Aging of the rubber bearing was reproduced by thermal degradation, where the target aging period was 30 years and 60 years. The load deflection curves of the thick rubber bearing after aging were obtained through the horizontal and vertical static loading tests, and the aging effect was evaluated by comparing with the initial mechanical properties.
Yamamoto, Tomohiko; Kawasaki, Nobuchika; Fukasawa, Tsuyoshi*; Okamura, Shigeki*; Somaki, Takahiro*; Samejima, Yusuke*; Masaki, Nobuo*
Proceedings of 2015 ASME Pressure Vessels and Piping Conference (PVP 2015) (Internet), 7 Pages, 2015/07
Since a SFR (Sodium-cooled Fast Reactor) has thin-walled component structures, a seismic isolation system is employed to mitigate the seismic force. Seismic isolation system for applying the SFR consists of the laminated rubber bearing considering characteristics of SFR structures. This paper describes a basic mechanical characteristic examination with a 1/8 scale model and a characterization examination plan of half-scale laminated rubber.
Fukasawa, Tsuyoshi*; Okamura, Shigeki*; Yamamoto, Tomohiko; Kawasaki, Nobuchika; Somaki, Takahiro*; Sakurai, Yu*; Masaki, Nobuo*
Proceedings of 2015 ASME Pressure Vessels and Piping Conference (PVP 2015) (Internet), 10 Pages, 2015/07
This paper described the results of static loading tests using a half-scale rubber bearing model to investigate the fundamental characteristics such as restoring force of a rubber bearing applied to a Sodium-Cooled-Fast-Reactor (SFR). Since the SFR has thin-walled structures, a seismic isolation system is employed to mitigate the seismic force. The static loading tests were performed using the half-scale rubber bearing with a diameter of 800 mm in the range which exceeds a linear limit of horizontal direction and a yield stress of vertical direction to investigate the horizontal and vertical of each stiffness and damping ratio. The fundamental characteristic of rubber bearing employed to the SFR and the validity of a design formula became clear through the static tests.
Negishi, Kazuo; Hosoya, Takusaburo; Sato, Kenichiro*; Somaki, Takahiro*; Matsuo, Ippei*; Shimizu, Katsusuke*
Proceedings of 2009 International Congress on Advances in Nuclear Power Plants (ICAPP '09) (CD-ROM), p.9418_1 - 9418_7, 2009/05
An innovative containment vessel, namely Steel plate reinforced Concrete Containment Vessel (SCCV) is developed for Japan Sodium-Cooled Fast Reactor (JSFR). Reducing plant construction cost is one of the most important issues for commercialization of fast reactors. This study investigated construction issues including the building structure and the construction method as well as design issues in terms of the applicability of SCCV to fast reactors. An experimental study including loading and/or heating tests has been carried out to investigate the fundamental structural features, which would be provided to develop methodology to evaluate the feasibility of SCCV under the severe conditions. In this paper, the test plan is described as well as the first test results.
Kitamura, Seiji; Okamura, Shigeki; Takahashi, Kenji; Kamishima, Yoshio*; Somaki, Takahiro*; Morishita, Masaki
Proceedings of 9th World Seminar on Seismic Isolation, Energy Dissipation and Active Vibration Control of Structures (CD-ROM), p.209 - 216, 2005/00
A structural concept of a vertical component isolation system for fast reactors, assuming a building adopting a horizontal base isolation system, has been studied. In this concept, a reactor vessel and major primary components are suspended from a large common deck supported by vertical isolation devices consisting of large coned disk springs. We designed the isolation device, which could be achieved vertical isolation frequency of 1 Hz and damping ratio of 20 %. Full scale coned disk spring and damper performance tests were carried out to verify the validity of design equations. And a series of shaking table test using a 1/8 scale model was performed. The test results fit well the simulation analysis results, so the validity of the design methods was able to be verified. The prospect that the vertical component isolation system applied to the FBR plant could technically realize was obtained.
Somaki, Takahiro*; Miyamoto, Akinori*
JNC TJ9410 2005-001, 101 Pages, 2004/11
JNC-TJ9410-2005-001.pdf:5.17MB
In this study, supporting structure for the seismic horizontal force and the common deck structure were taken concrete shapes, and the feasibility studies were carried out. Furthermore, the influence on design method of coned disk spring by creep phenomenon was investigated, test pieces for investigating the long-range stability of friction coefficient were manufactured.
Somaki, Takahiro*; Miyamoto, Akinori*
JNC TJ9420 2003-005, 129 Pages, 2003/02
JNC-TJ9420-2003-005.pdf:4.62MB
In order to realize the concept of a vertical isolation system called common deck system, research and development on the vertical isolation structure is now underway. In its first step, structure plans of each of the isolation element and the damper element will be drawn up, and in the next step, tests on these elements will be planed, executed, analyzed, and evaluated, to be reflected to the structure plan. In this report, the study of analysis, the structure plan and test plan of vertical isolation devices is reported. /The appropriateness of analysis was confirmed by comparison between test results and analysis results. And the loading mechanism and the stress condition of dish spring as piling five lines were analyzed./The formula of Creep was examined on creep test results. And the influence of amount of deformation by creep behavior was made clear on the life of building./The characteristic of loading in actual typical model was presumed by test results, design formula and FEM analysis. These results were mostly coincided and the appropriateness of design method was confirmed./Response displacement of a vertical isolation and response acceleration of primary instruments were analyzed and confirmed beyond restriction values by dynamic analysis./The total fabrication of isolation device and each component were drowned on the result of these studies./The scale of test model was estimated and the map of test model was drowned. And several test plans reflects design guideline were made.
Somaki, Takahiro*; Miyamoto, Akinori*; *
JNC TJ9420 2003-001, 341 Pages, 2003/01
JNC-TJ9420-2003-001.pdf:1.18MB
In order to realize the concept of a vertical isolation system (common deck system), research and development on the vertical isolation structure is now underway. In its first step, structure plans of each of the isolation element and the damper element will be drawn up, and in the next step, tests on these elements will be planed, executed, analyzed, and evaluated, to be reflected to the structure plane. In this report, the structure plan and test plan of damper element is reported. At first, it was concluded in the previous work that the steel-materials damper which can be evaluated by Ramberg-Osgood type is applicable to the vertical isolation system required performance.
Kitamura, Seiji; Okamura, Shigeki; Somaki, Takahiro*
no journal, ,
The three dimension seismic isolation system by the vertical component seismic isolation system with the coned disk springs is developed. In this report, the behavior of the coned disk spring with damage in loading test is described.
Kato, Atsushi; Negishi, Kazuo; Sato, Kenichiro*; Akiyama, Yo*; Hara, Hiroyuki*; Iwasaki, Mikinori*; Abe, Ganji*; Tokiyoshi, Takumi*; Okafuji, Takashi*; Umeki, Katsuhiko*; et al.
no journal, ,
Report research and development activities related to steel plate reinforced concrete containment vessel for the JSFR conducted as a part of METI commissioned research.
Kato, Atsushi; Negishi, Kazuo; Akiyama, Yo*; Iwasaki, Mikinori*; Okafuji, Takashi*; Abe, Ganji*; Somaki, Takahiro*; Umeki, Katsuhiko*; Fukushima, Yasuaki*; Sawamoto, Yoshikazu*
no journal, ,
Steel plate reinforced concrete structure are adopted as the JSFR containment vessel to shorten a construction period. This reports project summary of SCCV Research and Development.
Kato, Atsushi; Negishi, Kazuo; Hara, Hiroyuki*; Somaki, Takahiro*
no journal, ,
Japan Sodium-cooled Fast Reactor (JSFR) adopts a new concept of a containment vessel called steel plate reinforced concrete containment vessel (SCCV). The SCCV is considered to be effective to shorten construction schedule thanks for elimination of rebar work at a site compared with applying the reinforced concrete CV. JAEA has been investigating its characteristics under high thermal load to adopt the SC structure to a CV. This paper mainly describes the experimental study on SCCV bearing wall against lateral load.
Kato, Atsushi; Hara, Hiroyuki*; Takami, Shinji*; Somaki, Takahiro*
no journal, ,
Japan Sodium-cooled Fast Reactor (JSFR) adopts a new concept of a containment vessel called steel plate reinforced concrete containment vessel (SCCV). The SCCV is considered to be effective to shorten construction schedule thanks for elimination of rebar work at a site compared with applying the reinforced concrete CV. JAEA has been investigating its characteristics under high thermal load to adopt the SC structure to a CV. This paper mainly describes the experimental study on SCCV out-of-plane bending property.
Yamamoto, Tomohiko; Fukasawa, Tsuyoshi*; Somaki, Takahiro*; Hirokawa, Atsushi*; Miyagawa, Takayuki*; Okamura, Shigeki*
no journal, ,
High speed type horizontal oil damper is developed for three dimensional seismic isolation system for SFR. This paper describes the experimental plan of this oil damper.
Yamamoto, Tomohiko; Fukasawa, Tsuyoshi*; Somaki, Takahiro*; Hirokawa, Atsushi*; Miyagawa, Takayuki*; Okamura, Shigeki*
no journal, ,
no abstracts in English
Adachi, Yoshihiko*; Endo, Naoki*; Fukasawa, Tsuyoshi*; Somaki, Takahiro*; Miyagawa, Takayuki*; Yamamoto, Tomohiko; Okamura, Shigeki*
no journal, ,
no abstracts in English
Endo, Naoki*; Adachi, Yoshihiko*; Fukasawa, Tsuyoshi*; Somaki, Takahiro*; Miyagawa, Takayuki*; Yamamoto, Tomohiko; Okamura, Shigeki*
no journal, ,
no abstracts in English
Somaki, Takahiro*; Morobishi, Ryota*; Fukasawa, Tsuyoshi*; Miyagawa, Takayuki*; Yamamoto, Tomohiko; Okamura, Shigeki*
no journal, ,
no abstracts in English
Morobishi, Ryota*; Somaki, Takahiro*; Fukasawa, Tsuyoshi*; Miyagawa, Takayuki*; Yamamoto, Tomohiko; Okamura, Shigeki*
no journal, ,
no abstracts in English
