Estimation of Maximum Bending Moment at FPSO Bow Considering Slamming in External Turret Mooring

The external turret system is widely used for mooring of Floating Production, Storage and Offloading system (FPSO). Slamming is one of important issues which should be considered for designing FPSOs because FPSOs must stay in the same area even if those are under harsh conditions such as a storm. In response to cases of accidents caused by slamming, such as Schiehallion, a series of research projects were conducted in Europe, which proposed that the simplified estimation method of maximum slam force; however, it was too simplified to be used for detailed design. In this paper, the authors present the extreme value estimation of maximum bending moment including the slamming effect at the connection between the FPSO bow and the external turret lever. The foundation of the estimation method is based on the time-domain simulation by using the simulation model which was validated by comparing the results of the simulations with those of model tests. The simulation model was validated through comparison between model test results and the simulations. Two estimation methods for the expected value of 3 hour-maximum bending moment using the validated simulation model were investigated; one was the way of averaging maxima in multiple simulations, and another was due to extreme value analyses by four kinds of methods. As a result, the first method required more than 30 simulations; for the second method, the generalized Pareto distribution was the most suitable for extreme value analysis.

• Record URL:
  https://doi.org/10.2534/jjasnaoe.33.87
• Record URL:
  https://www.jstage.jst.go.jp/article/jjasnaoe/33/0/33_87/_pdf
• 
• Record URL:
  https://scholar.google.com/scholar_lookup?title=Estimation%20of%20Maximum%20Bending%20Moment%20at%20FPSO%20Bow%20Considering%20Slamming%20in%20External%20Turret%20Mooring&author=Y.%20Ishihara&author=S.%20Kato&author=M.%20Murai&author=Y.%20Nakajima&publication_year=2021
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/18803717
• Authors:
  • Ishihara, Yuki
  • Kato, Shunji
  • Murai, Motohiko
  • Nakajima, Yasuharu
• Publication Date: 2021

Language

• English
• Japanese

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; References; Tables;
• Pagination: pp 87-96
• Serial:
  • Journal of the Japan Society of Naval Architects and Ocean Engineers
  • Volume: 33
  • Publisher: Japan Society of Naval Architects and Ocean Engineers
  • ISSN: 1880-3717
  • EISSN: 1881-1760
  • Serial URL: https://www.jstage.jst.go.jp/browse/jjasnaoe/-char/en
• Publication flags:

  Open Access (libre)

Subject/Index Terms

• TRT Terms: Bending moments; Bows; Floating structures; Mooring; Slamming
• Subject Areas: Design; Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 01784479
• Record Type: Publication
• Source Agency: Japan Science and Technology Agency (JST)
• Files: TRIS, JSTAGE
• Created Date: Oct 8 2021 9:45AM