• Title/Summary/Keyword: KOCED

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Dynamic characteristics of single door electrical cabinet under rocking: Source reconciliation of experimental and numerical findings

  • Jeon, Bub-Gyu;Son, Ho-Young;Eem, Seung-Hyun;Choi, In-Kil;Ju, Bu-Seog
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2387-2395
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    • 2021
  • Seismic qualifications of electrical equipment, such as cabinet systems, have been emerging as the key area of nuclear power plants in Korea since the 2016 Gyeongju earthquake, including the high-frequency domain. In addition, electrical equipment was sensitive to the high-frequency ground motions during the past earthquake. Therefore, this paper presents the rocking behavior of the electrical cabinet system subjected to Reg. 1.60 and UHS. The high fidelity finite element (FE) model of the cabinet related to the shaking table test data was developed. In particular, the first two global modes of the cabinet from the experimental test were 16 Hz and 24 Hz, respectively. In addition, 30.05 Hz and 37.5 Hz were determined to be the first two local modes in the cabinet. The high fidelity FE model of the cabinet using the ABAQUS platform was extremely reconciled with shaking table tests. As a result, the dynamic properties of the cabinet were sensitive to electrical instruments, such as relays and switchboards, during the shaking table test. In addition, the amplification with respect to the vibration transfer function of the cabinet was observed on the third floor in the cabinet due to localized impact corresponding to the rocking phenomenon of the cabinet under Reg.1.60 and UHS. Overall, the rocking of the cabinet system can be caused by the low-frequency oscillations and higher peak horizontal acceleration.

Development of a 3D Model-Based Demonstration DB System for Efficient Management and Utilization of Inspection and Diagnosis Data of Small and Medium-Sized Bridges (중소규모 교량의 점검·진단 데이터 효율적 관리 및 활용을 위한 3D 모델 기반 실증 DB시스템 개발)

  • Park, Se-Hyun;Jung, Dae-Sung;Seo, Jin-Sook;Kim, Tae-Hyeong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.6
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    • pp.1-11
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    • 2021
  • As the aging of large domestic SOC facilities accelerates, facility maintenance is also changing from safety evaluation based on the current condition to performance-oriented preventive and preemptive maintenance based on the prediction of the level of future obsolescence. In particular, in the case of bridges, class 1 and 2 bridges are systematically managed along with many studies, but for small and medium-sized class 3 bridges there is no collection and utilization of historical data presenting performance degradation during their service life. Therefore, in this study, 3D model-based demonstration DB system was designed and developed to intuitively check the damage change rate at the damage location by registering the maintenance history by life cycle for each member's exterior damage in the 3D bridge object and to enable API-based comprehensive performance evaluation.