Study on Prediction Method for Spring-Induced Tension Responses of TLP

Springing을 고려한 TLP의 장력 예측 기법 연구

  • Received : 2014.06.19
  • Accepted : 2014.10.24
  • Published : 2014.10.31


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.


TLP;Springing;Tension prediction;Extreme value;Probability density function


  1. Eatock Taylor, R., Kernot, M.P., 1999. On Second Order Wave Loading and Response in Irregular Seas. Advances in Coastal and Ocean Engineering, 5, World Scientific, Singapore.
  2. Chen, X.B., 2007. Middle-field Formulation for the Computation of Wave-drift Loads, Journal of Engineering Mathematics, 59(1), 61-82.
  3. De Boom, W.C., Pinkster, J.A., Tan, P.S.G., 1983. Motion and Tether Force Prediction for a Deep Water Tension Leg Platform. Proceedings of Offshore Technology Conference, Houston, USA.
  4. Eatock Taylor, R., Jefferys, E.R., 1986. Variability of Hydrodynamic Load Prediction for a Tension Leg Platform. Ocean Engineering, 13(5), 449-490.
  5. Gie, T.S., De Boom, W.C., 1981. The wave induced motions of a tension leg platform in deep water. Proceedings of Offshore Technology Conference, Houston USA.
  6. Kac, M., Siegert, A.J.F., 1947. An Explicit Representation of a Stationary Gaussian Process. Annals of Mathematical Statistics, 18, 438-442.
  7. Kim, C.H., Zhao, C., Zou, J., 1995. Springing and Ringing Due to Nonlinear Waves on a Coupled TLP. Proceedings of International Offshore and Polar Engineering Conference, Hague, Netherlands, 83-89.
  8. Kim, C.H., 2008. Nonlinear Waves and Offshore Structures. World Scientific, Singapore.
  9. Kim, M.H., Yue D.K.P., 1991. Sum- and difference -frequency wave loads on a body in unidirectional Gaussian seas. Journal of Ship Research, 35(2), 127-140.
  10. Kim, T., Seo, M.G., Park, D.M., Kim, K.H., Kim, Y., 2012. Numerical Analysis on Motion Reponses and Wave Loads on Offshore Structures by Using a Time-domain Rankine Panel Method. Proceedings of Joint Conference with Korean Association of Ocean Science and Technology Societies, Daegu, Korea, 1393-1396.
  11. Matsui, T., Suzuki, T., Sakoh, Y., 1992. Second-order Diffraction Forces on Floating Three-dimensional Bodies in Regular Waves. International Journal of Offshore and Polar Engineering, 2(3), 175-185.
  12. Matsui, T., Sakoh, Y., Nozu, T., 1993. Second-order Sum-frequency Oscillations of Tension-leg Platforms: Prediction and Measurement. Applied Ocean Research, 15(2), 107-118.
  13. Naess, A., Ness, G.M., 1992. Second-order Sum-Frequency Response Statistics of Tethered Platforms in Random Waves. Applied Ocean Research, 14(1), 23-32.
  14. Naess, A., 1994. Statistics of Combined Linear and Quadratic Springing Response of a TLP in Random Waves. Journal of Offshore Mechanics and Arctic Engineering, 116(3), 127-136.
  15. Neal, E., 1974. Second-order Hydrodynamic Forces Due to Stochastic Excitation. Proceedings of Symposium on Naval Hydrodynamics, Cambridge, USA, 517-537.
  16. Ochi, M.K., 1998. Ocean Waves. Cambridge University Press, United Kingdom.
  17. Pan, Z.Y., Vada, T., Hanssen, F.C.W., 2013. A mesh Dependency Study for Mean Drift Forces by Pressure Integration. Proceedings of International Conference on Ocean, Offshore and Arctic Engineering, Nantes, France.
  18. Zou, J., Ormberg, H., Stansberg, C.T., 2004. Prediction of TLP Responses: Model Tests vs. Analysis. Proceedings of Offshore Technology Conference, Houston USA, 83-89.


Grant : 심해 석유 생산망 FEED 설계 및 부유체 핵심 기술 개발

Supported by : 산업통상자원부