Ocean Systems Engineering

  • 제14권1호
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  • Pages.1-16
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  • 2024
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  • 2093-6702(pISSN)
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  • 2093-677X(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

Effect of local joint flexibility on the fatigue lfe assessment of jacket-type offshore platform

  • Behrouz Asgarian (Faculty of Civil Engineering, K.N. Toosi University of Technology) ;
  • Parviz Kuzehgar (Faculty of Civil Engineering, K.N. Toosi University of Technology) ;
  • Pooya Rezadoost (Faculty of Civil Engineering, K.N. Toosi University of Technology)
  • 투고 : 2023.10.23
  • 심사 : 2023.12.18
  • 발행 : 2024.03.25
⟨ 이전 논문 다음 논문 ⟩

초록

This paper investigates the impact of local joint flexibility (LJF) on the fatigue life of jacket-type offshore platforms. Four sample platforms with varying geometric properties are modeled and analyzed using the Opensees software. The analysis considers the LJF of tubular joints through the equivalent element and flexible link approaches, and the results are compared to rigid modeling. Initially, modal analysis is conducted to examine the influence of LJF on the frequency content of the structure. Subsequently, fatigue analysis is performed to evaluate the fatigue life of the joints. The comparison of fatigue life reveals that incorporating LJF leads to reduced fatigue damage and a significant increase in the longevity of the joints in the studied platforms. Moreover, as the platform height increases, the effect of LJF on fatigue damage becomes more pronounced. In conclusion, considering LJF in fatigue analysis provides more accurate results compared to conventional methods. Therefore, it is essential to incorporate the effects of LJF in the analysis and design of offshore jacket platforms to ensure their structural integrity and longevity.

키워드

과제정보

The authors gratefully acknowledge the useful comments of anonymous reviewers on the draft version of this paper.

참고문헌

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