Transactions of the Korean Society of Pressure Vessels and Piping (한국압력기기공학회 논문집)

Korean Society of Pressure Vessels and Piping (한국압력기기공학회)
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Leak Before Break Evaluation of Surge Line by Considering CPE under Beyond Design Basis Earthquake

설계초과지진시 CPE를 고려한 밀림관 파단전누설 평가

  • 김승현 (한국전력기술(주) 원자로설계개발단) ;
  • 김연정 (한국전력기술(주) 원자로설계개발단) ;
  • 이한걸 (한국전력기술(주) 원자로설계개발단) ;
  • 강선예 (한국전력기술(주) 원자로설계개발단)
  • Received : 2021.11.19
  • Accepted : 2022.06.20
  • Published : 2022.06.30
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Abstract

Nuclear Power Plants (NPP) should be designed to have sufficient safety margins and to ensure seismic safety against earthquake that may occur during the plant life time. After the 9.12 Gyeongju earthquake accident, the structural integrity of nuclear power plants due to the beyond design basis earthquake is one of key safety issues. Accordingly, it is necessary to conduct structural integrity evaluations for domestic NPPs under beyond design basis earthquake. In this study, the Level 3 LBB (Leak Before Break) evaluation was performed by considering the beyond design basis earthquake for the surge line of a OPR1000 plant of which design basis earthquake was set to be 0.2g. The beyond design basis earthquake corresponding to peak ground acceleration 0.4g at the maximum stress point of the surge line was considered. It was confirmed that the moment behaviors of the hot leg and pressurized surge nozzle were lower than the maximum allowable loading in moment-rotation curve. It was also confirmed that the LBB margin could be secured by comparing the LBB margin through the Level 2 method. It was judged that the margin was secured by reducing the load generated through the compliance of the pipe.

Keywords

Acknowledgement

본 논문은 한국에너지기술평가원(KETEP)의 지원으로 수행한 연구과제(No.20193110100020)의 결과입니다.

References

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