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Choi, B.; Nishida, Akemi; Muramatsu, Ken*; Takada, Tsuyoshi*
Transactions of the 24th International Conference on Structural Mechanics in Reactor Technology (SMiRT-24) (USB Flash Drive), 10 Pages, 2017/08
In order to clarify the influence of the modeling method on the result of seismic response analysis of nuclear facility, seismic response analysis using various simulated input ground motions was carried out and the uncertainty of response results were statistically analyzed. In particular, we focused on the difference of the response due to the structural modeling method (a conventional sway-rocking model and 3D FE model), and the relations among the input level, floor position, and response results were described and discussed.
Tanai, Kenji; Horita, M.*; Dewa, Katsuyuki*; Goke, Mitsuo*
JNC TN8410 2001-026, 116 Pages, 2002/03
JNC-TN8410-2001-026.pdf:9.19MB
Earthquake resistance for the underground structure is higher than the ground structure. Therefore, the case of examining the earthquake resistance of underground structure was little. However, it carries out the research on the aseismic designing method of underground structure, since the tunnel was struck by Hyogo-ken Nanbu Earthquake, and it has obtained a much knowledge. However, an object of the most study was behavior at earthquake of the comparatively shallow underground structure in the alluvial plain board, and it not carry out the examination on behavior at earthquake of underground structure in the deep rock mass. In the meantime, underground disposal facility of the high level radioactive waste constructs in the deep underground, and it carries out the operation in these tunnels. In addition, it has made almost the general process of including from the construction start to the backfilling to be about 60 years (Japan Nuclear Fuel Cycle Development Institute, 1999). During these periods, it is necessary to also consider the earthquake resistance as underground structure from the viewpoint of the safety of facilities. Then, it extracted future problem as one of the improvement of the basis information for the decision of the safety standard and guideline of the country on earthquake-resistant design of the underground disposal facility, while it carried out investigation and arrangement of earthquake-resistant design cases, guidelines and analysis method on existing underground structure, etc.. And, the research item for the earthquake resistance assessment of underground structure as case study of the underground research laboratory.
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JNC TN9400 2000-060, 168 Pages, 2000/05
JNC-TN9400-2000-060.pdf:4.09MB
Optimal vertical isolation characteristics were studied for the structural concept of vertical seismic isolation system, which uses a common deck and a set of large coned dish springs. Four kinds of earthquake wave and three kinds of artificial seismic wave were used. The earthquake response analysis of a base isolated building was carried out considering some ground conditions and some vertical vibration characteristics of the building isolator. Floor response and acceleration time history at the vertical isolation level were arranged. Using the acceleration time history as a seismic input, the earthquake response analysis of the vertical isolation system according to single degree of freedom model was carried out. Linear analysis and non-linear analysis were made. ln the linear analysis, vertical isolation frequency was examined within 0.8 to 2.5 Hz, and damping ratio was examined within 2 to 60%. ln the non-linear analysis, it was examined within vertical isolation frequency 0.5 to 5Hz, which depended only on the rigidity of the coned disk spring, rigidity ratio of the damping devise 1 to 20 and yield seismic intensity of the damping devise 0.01 to 0.2. As the optimal vertical isolation characteristics of the system, the criterion of largest relative displacement, maximum acceleration and maximum value of the floor response acceleration between 5 to 12Hz was set, the combination region of the appropriate parameter were examined. ln case of largest relative displacement 50mm, acceleration response magnification of 0.75, floor response magnification of 0.33 were used as a criterion, from the result of the linear analysis, vertical frequency was set at 0.8 to l.2 Hz, and by combining the damping ratio over 20 %, it was proven that appropriate vertical isolation characteristics were obtained. The result of the non-linear analysis showed that the combination of the coned disk spring of vertical frequency 0.8 to 1.0 Hz and the damping element of rigidity ...
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JNC TJ9440 2000-007, 43 Pages, 2000/03
JNC-TJ9440-2000-007.pdf:1.73MB
Planning of the plutonium utihzation in the Light water thermal reactor has been investigated to evaluate scenario for FBR development. Plans for MOX fuel utilization in the ABWR including Ooma plant are studied, and information of high burnup fuels for a future BWR is summarized based on public documents. Nuclear compositions of the present burnup fuel (45,000MWd/t) and a high burnup fue (60,000MWd/t) have been evaluated using an open code: SRAC. Results of the study are follows; (1)Surveying the status of MOX fuel utilization. The status of MOX and UO
fuel utilization in the present BWR and future BWR have been summarized based on public documents. (2)Evaluation of spent MOX and UO fuel composition. Nuclear compositions of spent MOX and UO fuels at 45,000MWd/t and 60,000MWd/t burnup have been evaluated and summarized for recycle scenarios by FBR.
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JNC TJ3410 2000-021, 73 Pages, 2000/03
JNC-TJ3410-2000-021.pdf:52.78MB
no abstracts in English
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JNC TJ3410 2000-020, 80 Pages, 2000/03
JNC-TJ3410-2000-020.pdf:41.34MB
no abstracts in English
Isozaki, Kazunori;
PNC TN9410 97-069, 134 Pages, 1997/07
Hyougo-ken southern earthquake broke out in 1997/01/17. The Atomic Energy Safety Co㎜ission considered reasonable of the design guide for seismic design. And the Science and Technology Agency(STA) required reevaluation of atomic power facilities built by old design guide according to the new seismic design guide. JOYO obtained the construction license in 1970/02. Heat transport system and buildings of JOYO was reevaluated by the new seismic design guide for the MK-III project. So, JOYO was not required reevaluation by STA. But, this evaluation of MK-III was limited to reconstruction area, and the seismic design was reevaluated extensively to confirm earthquake proof characteristics. The structural integrity of buildings and equipments was confirmed by the result of reevaluation by the new seismic design guide. The analysis model conditions were established according to the 1987 and 1991 version of JEAG. This was done by ground investigation result and buildings vaibration test. It was made clear that the analysis model conditions were reasonable and conservative from a technical view point.
PNC TN9410 97-032, 126 Pages, 1997/04
Study was made on the effect of dynamic interaction between reactor building and common deck isolation structure. Dynamic response analyses were made with a coupled and a decoupled model of the reactor building and the isolation structure. The effect of the dynamic interaction was evaluated by comparing these analysis results. The results of the study can be summarized as below; (1)Dynamic coupling effect between reactor building and the common deck isolation structure is not significant. This can be attributed to the fact that the isolation frequency is sufficiently lower than the fundamental frequency of the soil-structure system. (2)The decoupled analysis model was found to give response results with practically sufficient accuracy and slight conservatism. (3)The effect of the response of common deck isolation structure on the response of the reactor building is also negligible.
; *; *; *; Abe, Kiyoharu
JAERI-Research 96-059, 73 Pages, 1996/11
JAERI-Research-96-059.pdf:2.72MB
no abstracts in English
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PSA95: Proc. of Probabilistic Safety Assessment Methodology and Applications, 2, p.715 - 720, 1995/00
no abstracts in English
Choi, B.; Nishida, Akemi; Guo, Z.; Yamano, Hidemasa; Takada, Tsuyoshi*
no journal, ,
In this research, the seismic safety of nuclear power plants (NPPs) is treated as a system, in which the various cliff edge effects are identified and quantified based on the concepts of risk and defense in depth, and a methodology is then developed for avoiding these cliff edge effects. As the first step, preliminary elastic-plastic analyses of the NPP building system are carried out, and knowledges on the dependency of cliff edge effects on various modeling factors are obtained. Based on these knowledges, preliminary fragility evaluations of the reactor vessel and piping are carried out, and the effectiveness of a horizontal seismic isolation system against the cliff edges is addressed.
Horiguchi, Naoki; Miyahara, Naoya; Uesawa, Shinichiro; Yoshida, Hiroyuki; Osaka, Masahiko
no journal, ,
As a basic study to develop an evaluation method for aerosol deposition amounts in a containment vessel and a reactor building during LWR severe accident, to understand the tendency of the aerosol particle deposition and the decontamination factor, the behavior of the leaked aerosol from the reactor in the building was simulated by CFD on simplified condition of the building shape and the flow. As a result, the basic knowledge associated to the transportation and the deposition of the aerosol particles in the building was obtained, which is the possibility of the significant deposition for the decontamination in the building, and the tendency that the bigger aerosol particles is, the easier they deposit on the lower floors and the higher the decontamination factor becomes.
Horiguchi, Naoki; Miyahara, Naoya; Uesawa, Shinichiro; Yoshida, Hiroyuki; Osaka, Masahiko
no journal, ,
Development of a CFD-based analysis method of aerosol deposition amounts in a reactor building has been conducted to contribute to realistic source term evaluation. In order to establish one of the aerosol deposition models at specific structures in a reaction building, preliminary analysis of aerosol deposition amount when passing through a narrow flow channel, namely a door, was conducted. Results showed that aerosol deposition amount increased as the pressure difference between inlet and outlet and the particle diameter increased due to the increase of inertia force of the particles. These results can be important knowledge for the modelling.
Horiguchi, Naoki; Uesawa, Shinichiro; Yoshida, Hiroyuki
no journal, ,
Evaluation method based on CFD and particle tracking method for aerosol particle depositon in a reactor building during severe accident has been developed. In order to construct of prediction model of particle deposition in a narrow channel for reduction of numerical simulation cost in the evaluation method, some numerical simulations with each representative components of the narrow channel, a straight, a bend, a nozzle and a diffuser part were conducted. In case of the bend part, behavior of air and CsI particles under steady flow were simulated with parameters, particle diameter, pressure difference between inlet and outlet of a modeled channel and width of the channel. As results of particle deposition rate based on the numerical simulation, increase tendences of particle depositon rate with increase of particle diameter were changed with increase of pressure difference and decrease of width. These results can be important knowledge for the modelling.
Horiguchi, Naoki; Nakamura, Koichi*; Sekiguchi, Takashige*; Uesawa, Shinichiro; Himi, Masashi*; Yoshida, Hiroyuki; Nishimura, Satoshi*
no journal, ,
no abstracts in English
Hara, Hiroyuki*; Tamura, Shogo*; Yamamoto, Tomohiko
no journal, ,
no abstracts in English