Stochastic Response of Coupled Platform-Tether System Under Multi-Directional Seas

  • Ahsan Kareem
  • Xiaobing Song
Conference paper
Part of the Solid Mechanics and its Applications book series (SMIA, volume 47)

Abstract

A tension leg platform consists of a floating top platform which is kept in position by vertical tensioned cables referred to as tethers. The overall platform motions can be divided into two categories, e.g., vertical plane and horizontal plane motions. The horizonal plane motions, namely, surge, sway and yaw have a very low frequency which classifies these motions as compliant in nature, whereas, the vertical plane motions, pitch, roll and heave are relatively high frequency. By virtue of their compliant behavior in the horizontal plane, TLPs are less sensitive to loads at the wave-frequency, but their sensitivity to low frequency loads (e.g., wind and slowly varying second-order wave loads) increases. The level of low-frequency loads, though small in comparison with the wave-frequency loads, contributes significantly to the platform response. In a similar manner the vertical plane motions are more sensitive to second- and higher-order effects of waves than the first-order effects and result in spring and ringing types of motion.

Keywords

Wave Force Wave Load Frequency Domain Analysis Stochastic Response Frequency Domain Approach 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Ahsan Kareem
    • 1
  • Xiaobing Song
    • 2
    • 3
  1. 1.University of Notre DameNotre DameUSA
  2. 2.University of HoustonUSA
  3. 3.Ludwig Buildings IncNew OrleansUSA

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