Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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Reliability-based Flaw Assessment of a Mooring Chain Using FORM and SORM

FORM 및 SORM을 이용한 무어링 체인의 신뢰성 기반 결함평가

  • Lee, Choong-Hyun (Department of Naval Architecture and Ocean Engineering, College of Engineering, INHA University) ;
  • Kim, Yooil (Department of Naval Architecture and Ocean Engineering, College of Engineering, INHA University)
  • 이충현 (인하대학교 공과대학 조선해양공학과) ;
  • 김유일 (인하대학교 공과대학 조선해양공학과)
  • Received : 2017.03.10
  • Accepted : 2017.09.20
  • Published : 2017.10.20
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Abstract

This study presents the reliability-based flaw assessment for the crack in the mooring chain of a floating type offshore structure. BSI(British Standard Institution) flaw assessment procedure BS7910 was combined with first- and second-order reliability method (FORM, SORM) so that the acceptance of a given flaw can be assessed considering the uncertainties of parameters that play important role in the flaw assessment. Considering the probabilistic nature of the crack size and long-term distribution of the stresses acting on the crack in mooring chain, the failure probability was calculated using FORM and SORM. To check the validity of the FORM and SORM, Monte Carlo simulation was also carried out to derive the true limit state function and compared with the results of FORM and SORM.

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References

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