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China Ocean Engineering

, Volume 32, Issue 5, pp 536–545 | Cite as

Strength Analysis on Brace Structure for Semi-Submersible in Consideration of Wave Slamming

  • Fa-li Huo
  • Zhi Yao
  • Jian Zhang
  • Jun-wei Wang
  • Bin Dong
Article
  • 21 Downloads

Abstract

Slamming on bracings of column stabilized units shall be considered as a possible limiting criterion under transit condition based on the requirements in DNV-OS-C103. However, the wave slamming loads under survival condition were ignored for the strength analysis of the brace structures in many semi-submersible projects. In this paper, a method of strength analysis of brace structure is proposed based on the reconstruction and extrapolation of numerical model. The full-scale mooring system, the wind, wave and current loads can be considered simultaneously. Firstly, the model tests of the semi-submersible platform in wind tunnel and wave tanker have been carried out. Secondly, the numerical models of the platform are reconstructed and extrapolated based on the results of model tests. Then, a nonlinear numerical analysis has been conducted to study the wave slamming load on brace in semi-submersible platform through the reconstructed and extrapolated numerical model. For the randomness of wave load, ten subcases under each condition have been carried out. The value of the 90% Gumble distribution values of the ten subcases are used. Finally, the strength on brace structure has been analyzed considering the wave slamming. The wave slamming loads have been compared between the survival condition and transit condition with the method. The results indicate that wave slamming under survival condition is more critical than that under transit condition. Meanwhile, the wave slamming is significant to the structural strength of the brace. It should be overall considered in the strength analysis of the brace structure.

Key words

semi-submersible platform wave slamming brace structure structural strength 

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Copyright information

© Chinese Ocean Engineering Society and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Fa-li Huo
    • 1
  • Zhi Yao
    • 1
  • Jian Zhang
    • 1
  • Jun-wei Wang
    • 2
  • Bin Dong
    • 2
  1. 1.School of Naval Architecture and Ocean EngineeringJiangsu University of Science and TechnologyZhenjiangChina
  2. 2.Grenland Group (China) Ltd.ShanghaiChina

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