Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Study on Prediction Method for Spring-Induced Tension Responses of TLP

Springing을 고려한 TLP의 장력 예측 기법 연구

  • Kim, Taeyoung (Department of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Kim, Yonghwan (Department of Naval Architecture and Ocean Engineering, Seoul National University)
  • 김태영 (서울대학교 조선해양공학과) ;
  • 김용환 (서울대학교 조선해양공학과)
  • Received : 2014.06.19
  • Accepted : 2014.10.24
  • Published : 2014.10.31
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Abstract

This paper considered the prediction of the tension force in the design of a TLP tendon, particularly focusing on the springing problem. Springing is an important parameter that exerts a large tension in special cases. It is a nonlinear phenomenon and requires the 2nd-order wave loads to solve. In this paper, a new prediction method for springing and the resultant extreme tension on the tendon of a TLP is introduced. Using the 2nd-order response function computed using the commercial program WADAM, the probability density function of the 2nd-order tension is obtained from an eigenvalue analysis using a quadratic transfer function and sea spectra. A new method is then suggested to predict the extreme tension loads with respect to the number of occurrences. It is shown that the PDF suggested in this study properly predicts the extreme tension in comparison with the time histories of the 2nd-order tension. The expected tension force is larger than that from a linear analysis in the same time windows. This supports the use of the present method to predict the tension due to springing.

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References

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