Applicability of the mα-tangent Method to Estimate Plastic Limit Loads of Elbows and Branch Junctions

선형탄성해석과 mα-tangent방법을 이용한 배관 한계하중 평가 적용성

  • 김재민 (고려대학교 기계공학부) ;
  • 김상현 (고려대학교 기계공학부) ;
  • 배경동 (고려대학교 기계공학부) ;
  • 김윤재 (고려대학교 기계공학부) ;
  • 김종성 (세종대학교 원자력공학과)
  • Received : 2016.10.27
  • Accepted : 2017.02.14
  • Published : 2017.06.01


In this study, the limit loads calculated by the $m_{\alpha}-tangent$ method based on the linear finite element analysis are compared with the closed form solutions that are proposed by various authors. The objects of the analysis is to select the elbow and the branch pipe which are representative structure of piping system. The applicability of the $m_{\alpha}-tangent$ method are investigated by applying it to cases with various geometries. The internal pressure and the in-plane bending moment are considered and the $m_{\alpha}-tangent$ method is in good agreement with the existing solutions in case of elbows. However, the limit loads calculated by the $m_{\alpha}-tangent$ method for branch junctions do not agree well with the existing solutions and do not show any tendency. The reason is a biased result due to the stress concentration of the discontinuous parts.


Supported by : 한국연구재단


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