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An Experimental Study on Fatigue Life Evaluation of Welded Joints under Storm Loading

스톰 하중을 받는 용접 구조물의 피로 수명 평가에 대한 실험 연구

  • Yoo, Chang-Hyuk (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Kim, Kyung-Su (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Suh, Yong-Suk (Samsung Heavy Industries Co. Ltd.) ;
  • Shim, Yong-Lae (ABS) ;
  • Ha, Yeong-Su (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • You, Won-Hyo (Department of Naval Architecture and Ocean Engineering, Inha University) ;
  • Choi, Hyun-Jun (Department of Naval Architecture and Ocean Engineering, Inha University)
  • Received : 2011.06.29
  • Accepted : 2012.01.19
  • Published : 2012.02.20

Abstract

In this paper, fatigue tests are conducted for the specimens with longitudinal and transverse attachment under variable amplitude axial loading based on storm model. Considered loadings include repeated single storm, 6 or 8 storms randomly, and storms including calm sea condition while the mean stress and the maximum stress of loadings are changed. The effect of three variables are investigated; root mean square(RMS) value of stress amplitude, mean stress shift and maximum stress, which can characterize storm loading on fatigue life. In addition, experiments including calm sea loading are also carried out to investigate the effect of calm sea state. Test results are evaluated and compared with DNV-CN2005 and Matsuoka's method for the estimation of crack initiation and propagation life. To verify the validity of the criteria, the measured crack initiation lifes are compared with the specific crack length 15mm, which are calculated with beach marks.

Keywords

References

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