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

The Society of Naval Architects of Korea (대한조선학회)
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A Study on Fatigue Analysis of Non-Gaussian Wide Band Process using Frequency-domain Method

주파수 영역 해석 기법을 이용한 비정규 광대역 과정의 피로해석에 관한 연구

  • Kim, Hyeon-Jin (Department of Naval Architecture and Ocean Engineering, College of Engineering, Seoul National University) ;
  • Jang, Beom-Seon (Research Institute of Marine Systems Engineering, Department of Naval Architecture and Ocean Engineering, College of Engineering, Seoul National University)
  • 김현진 (서울대학교 공과대학 조선해양공학과) ;
  • 장범선 (서울대학교 공과대학 조선해양공학과, 해양시스템 공학연구소)
  • Received : 2018.06.25
  • Accepted : 2018.08.17
  • Published : 2018.12.20
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Abstract

Most frequency domain-based approaches assume that structural response should be a Gaussian random process. But a lot of non-Gaussian processes caused by multi-excitation and non-linearity in structural responses or load itself are observed in many real engineering problems. In this study, the effect of non-Normality on fatigue damages are discussed through case study. The accuracy of four frequency domain methods for non-Gaussian processes are compared in the case study. Power-law and Hermite models which are derived for non-Gaussian narrow-banded process tend to estimate fatigue damages less accurate than time domain results in small kurtosis and in case of large kurtosis they give conservative results. Weibull model seems to give conservative results in all environmental conditions considered. Among the four methods, Benascuitti-Tovo model for non-Gaussian process gives the best results in case study. This study could serve as background material for understanding the effect of non-normality on fatigue damages.

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References

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