• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.498-498
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• 2001

Seismic qualification of the Main Control Boards for nuclear power plants has been performed with the guideline of AS ME Section III. US NRC Reg. Guide and IEEE 344 code. The analysis model of the Main Control Boards is consist of beam. shell and mass element by using the finite element method. and, at the same time. the excitation forces and other operating loads for each model are encompassed with respect to different loading conditions. As the fundamental frequencies of the structure are found to be less than 33Hz. which is the upper frequency limit of the seismic load, the response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the structural and functional integrity of the major components, modal analysis theory is adopted to derive the required response spectrum at the component locations. As all the combined stresses obtained from the above procedures are less than allowable stresses and no mechanical or electrical failures are found from the seismic testing, it concludes the Main Control Boards is dynamically qualified for seismic conditions. Although the authors had confirmed the structural and functional integrity of both Main Control Boards and all the component, in this paper only the seismic analysis of the Main Control Board is introduced.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.04a
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• pp.147-154
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• 1998

The purpose of this paper is to propose the draft guidelines of seismic isolation design of Liquid Metal Reactor (LMR) using high damping laminated rubber bearings. The scopes of guidelines include design requirements of a seismically isolated system and components, seismic isolator, isolation system, interface system between seismic isolation and non-seismic isolation part, qualification and acceptance tests of seismic isolator, seismic isolation reliability, and seismic safety and monitoring system. Proposed guidelines shall be revised to extend to general design guideline for nuclear facilities by further research and discussions.

• The KSFM Journal of Fluid Machinery
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• v.2 no.2 s.3
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• pp.13-18
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• 1999

The pump safety related to the functions in nuclear power plants must be designed to meet load conditions considering seismic requirements. In order to satisfy both structural integrity and operability of these pumps, the initial step in the seismic qualification is to establish the resonant frequencies of the structure. Applications we made to the design of the vertical and horizontal type pump. Computational results are analyzed with respect to the dynamic characteristics and are compared to the expected design requirements.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.6_spc
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• pp.697-704
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• 2016

The second shutdown drive mechanism (SSDM) that is classified into seismic category I as an active mechanical equipment shall maintain the structural integrity and its designed inherent safety functions during and/or after normal operation, anticipated operational occurrences, accidents and seismic occurrences. Therefore, not only a structural integrity assessment through numerical analyses but also a qualification test by using the prototype SSDM shall be conducted to verify the adequacy of the SSDM design. This paper describes a sort of seismic qualification test of the prototype SSDM to demonstrate that the structural integrity and operability (functionality) of SSDM are maintained during and/or after seismic excitations. From the results, this paper shows that the SSDM satisfies all design requirements without any malfunctions during and after the seismic test.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.5
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• pp.715-722
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• 2013

Gas insulated switchgear is large-sized electric equipment for providing a reliable supply of electric power. Recently, seismic tests of electric equipment using a shaking table have been mandated because seismic performance has become an increasingly important issue. However, basic analysis methods continue to be used because some electric equipment is too large for shaking table facilities. Thus, a reliable analysis method should be developed for large-scale electric equipment. This study aims to evaluate the seismic qualification of a 245kV GIS in accordance with IEEE-693 and to validate the analysis method by comparing it with test results. Both the test and the analysis showed that the 245kV GIS has proper seismic safety. Furthermore, the differences between the analysis and the test results are less than 10% for an accurately given mass, stiffness, and input acceleration. It is expected that this study can be used for the seismic qualification of large-scale electrical structures.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.239-249
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• 2002

The Turbine Building of nuclear power plant is classified as non safety-related structure. During the operation, there may be possibility the original licensing basis would be changed, which makes non safety-related structure safety-related. Such a change in regulation requires utility to perform seismic qualification for the existing structure and their facilities. Thus it is meaningful to evaluate seismic margin of the existing non-qualified building structure. In addition, in this paper it is shown that a modification to the structure can enhance their seismic capacity.

• Computational Structural Engineering
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• v.6 no.2
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• pp.79-86
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• 1993

A method to verify seismic qualification of the plant protection system cabinet for a nuclear power plant is presented. A finite element model of the cabinet is developed and the dynamic characteristics are obtained. The results of the modal analysis provide insight into the fundamental dynamic properties of the structure, which correspond to the frequency of the peak values of the input seismic spectrum. It necessitates the design modification of the reference cabinet. Techniques for verifying structural integrity and operability are exemplified by summarizing response spectrum and time history analyses of the structure.

• Journal of the Korean Society of Safety
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• v.13 no.4
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• pp.286-291
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• 1998

This paper includes discussion on developing the test verified finite element model for one of the seismic qualification(safety) approaches. It presents a test verified finite element model of a UPS(Uninterruptible Power Supply System) to be used at KMRR, KAERI. The test verified model predicts natural frequencies within 5 percent error for all major modes below 50Hz. This model accurately represents the dynamic characteristics of the actual hardware and is qualified for its use in the final stress analysis for seismic verification.

• Journal of Power System Engineering
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• v.10 no.4
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• pp.71-77
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• 2006

This study introduces the seismic qualification of safety related equipments for nuclear power plants to verify the possibility of resonance in regard to the operating speed and the structural integrity due to external piping nozzle loads as well as seismic dynamic loads using El-Centro earthquake, which was occurred in the 1940's previously. As a first step, it is necessary to investigate the natural frequency of the vertical mixed flow pump in order to determine whether static or dynamic equipment comparing with seismic cut-off frequency, 33hz. Also the normal mode analysis was carried out with the introduction of seismic redesign straint at the middle of vertical pump to increase the natural frequency. In terms of structural integrity, the application of static analysis with normal, upset and faulted nozzle loads event was presented for the comparison of material allowable stress. Also the dynamic analysis was performed to show the design adequacy through the application to the case of El-Centro earthquake.

• Journal of Korean Society of Steel Construction
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• v.27 no.3
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• pp.347-357
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• 2015

In this study, an experimental study was performed to evaluate the concrete breakout strength of unreinforced cast-in-place anchors by seismic qualification test under shear loading. The CIP anchors tested herein were 30mm in diameter with an edge distance of 150mm and an embedment depth of 240mm in uncracked and cracked concrete. The cracked specimen consisted of orthogonal and parallel crack to the loading direction, respectively. The dynamic loading sequence during the seismic qualification test was determined based on CSA N287.2, ACI 355.2 and ETAG 001 codes. After the dynamic loading, the static loading was applied until failure occurs. The shear resistance by seismic qualification tests showed almost the same strength as that obtained from the static tests in uncrcaked and cracked concrete, respectively. Meanwhile, the breakout depth did not reach $8d_0$, therefore the modified strength equation of ACI 318-11 could estimate properly the concrete breakout strength, which does not consider effective bearing length.