Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Comparison between Field Test and Numerical Analysis for a Jacket Platform in Bohai Bay, China

  • Yang He-Zhen (Division of Ocean Development Engineering, Korea Maritime University) ;
  • Park Han-Il (Division of Ocean Development Engineering, Korea Maritime University) ;
  • Choi Kyung-Sik (Division of Ocean Development Engineering, Korea Maritime University) ;
  • Li Hua-Jun (College of Engineering, Ocean University of China)
  • Published : 2006.04.01
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Abstract

This paper, presents a comparison between numerical analysis and field test on a real offshore platform in Bohai Bay, China. This platform is a steel jacket offshore platform with vertical piles. The field testing under wave-induced force and wind force etc. was conducted, in order to obtain the dynamic parameters of the structure, including the frequencies of the jacket platform, as well as the corresponding damping ratios and mode shapes. The natural excitation technology (NexT) combined with eigensystem realization algorithm (ERA) and the peak picking (PP) method in frequency domain are carried out for modal parameter indentification under operational conditions. The three-dimeansional finite element model (FEM) is constructed by ANSYS and analytical modal analysis is performed to generate modal parameters. The analytical results were compared with experimental results. A good agreement was achieved between the finite element and analysis and field test results. It is further demonstrated that the numerical and experimental modal analysis provide a comprehensive study on the dynamic properties of the jacket platform. According to the analysis results, the modal parameters identification under ambient excitation can calibrate finite element model of the jacket platform structures, or can be used for the structural health monitoring system.

Keywords

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