Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Limit State Assessment of SCH80 3-inch Steel Pipe Elbows Using Moment-Deformation Angle Relationship

모멘트-변형각의 관계를 이용한 SCH80 3인치 강재배관엘보의 한계상태 평가

  • 김성완 (부산대학교 지진방재연구센터) ;
  • 윤다운 (부산대학교 지진방재연구센터) ;
  • 정진환 (부산대학교 건설융합학부) ;
  • 김성도 (경성대학교 건설환경도시공학부)
  • Received : 2020.05.08
  • Accepted : 2020.06.29
  • Published : 2020.06.30
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Abstract

To conduct probabilistic seismic fragility analysis for nuclear power plants, it is very important to define the failure modes and criteria that can represent actual serious accidents. The seismic design criteria for piping systems, however, cannot fully reflect serious accidents because they are based on plastic collapse and cannot express leakage, which is the actual limit state. Therefore, it is necessary to clearly define the limit state for reliable probabilistic seismic fragility analysis. Therefore, in this study, the limit state of the SCH80 3-inch steel pipe elbow, the vulnerable part of piping systems, was defined as leakage, and the in-plane cyclic loading test was conducted. Moreover, an attempt was made to quantify the failure criteria for the steel pipe elbow using the damage index, which was based on the dissipated energy that used the moment-deformation angle relationship.

원자력발전소의 확률론적 지진취약도 분석을 수행하기 위해서는 실제 중대 사고를 표현할 수 있는 파괴모드와 파괴기준의 정의가 중요하다. 그러나 배관시스템의 내진설계기준은 소성붕괴로서 실제 한계상태인 누수를 표현하지 못하므로 중대 사고를 충분히 반영하지 못하고 있다. 따라서 신뢰성 있는 확률론적 지진취약도 분석을 위해서는 한계상태를 명확히 정의할 필요가 있다. 따라서 본 연구에서는 배관시스템의 취약부위인 SCH80 3인치 강재배관엘보의 한계상태를 누수로 정의하고 면내반복가력시험을 수행하였다. 또한 모멘트-변형각의 관계의 소산 에너지에 기반을 둔 손상도를 이용하여 강재배관엘보의 파괴기준을 정량화하고자 하였다.

Keywords

References

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