Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Nonlinear Finite Element Analysis for Mooring Chain Considering OPB/IPB

OPB/IPB를 고려한 계류체인의 비선형 수치해석

  • Kim, Min-suk (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Kim, Yooil (Department of Naval Architecture and Ocean Engineering, Inha University)
  • 김민석 (인하대학교 조선해양공학과) ;
  • 김유일 (인하대학교 조선해양공학과)
  • Received : 2017.01.16
  • Accepted : 2017.06.22
  • Published : 2017.08.31
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Abstract

The design of the mooring line to maintain the position of an offshore structure in rough marine environments is recognized as a very important consideration. Conventional fatigue evaluation of a mooring line was performed by considering the tensile force acting on the mooring line, but the mooring line broke after 238 days in the girassol area even though the expected fatigue life was expected to be longer. The causes of this event are known to be due to OPB/IPB (out-of-plane bending/in-plane bending) caused by chain link friction due to the excessive tensile strength of the mooring line. In this study, three models with different boundary conditions were proposed for fatigue analysis of a mooring line considering OPB/IPB. Interlink stiffness was calculated by nonlinear structure analysis and a stress concentration factor was derived. In addition, the sensitivity of interlink stiffness according to the magnitude of tensile force, large deformation effect, and coefficient of friction was analyzed, and the effect of critical elastic slip and bending moment calculation position on interlink stiffness was confirmed.

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References

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