• Journal of Power System Engineering
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• v.14 no.2
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• pp.48-54
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• 2010

An improved numerical scheme, to which the hydroelastic method is adapted, is introduced for predicting the motion and structural responses of tension leg platforms(TLPs) in regular waves. The numerical approach in this work is based on a combination of the three dimensional source distribution method and the finite element method. The hydrodynamic interactions among TLP members, such as columns and pontoons, are included in the motion and structural response analysis. The drag forces on the submerged slender members, which are proportional to the square of relative velocity, are included in order to estimate the responses of members with better accuracy. Comparisons with other results verify the works in this paper.

• Journal of Ocean Engineering and Technology
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• v.20 no.5 s.72
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• pp.82-88
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• 2006

This assessment is concerned with the fatigue strength of the tendon porch found in TLP. Lorge-scale fatigue tests with models constructed at 30% the size of the real structures have been carried out to investigate the fatigue behavior of the API 2W Grade 50 steel recently produced by POSCO. The fatigue life for the present test models was obtained based on the concept of nominal stress. A comparison of the present test results with those obtained by a numerical approach based on the structural analysis results has showngood agreement. The present results were also compared with the design curves in DnV RP-C203.

• Bulletin of the Society of Naval Architects of Korea
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• v.27 no.2
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• pp.55-62
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• 1990

In this paper, another method for system reliability analysis, called the extended incremental load method, is introduced. The method is an extension of the conventional incremental load method and has been developed aiming at evaluating the probability of system failure(or system reliability) of continuous structures such as floating offshore structures under the multiple loading condition, more realistically considering the post-ultimate behaviour of failed components and directly using the strength formulae of principle components in a structure with employing the modified safety margin equation proposed herein in the system analysis. The method has been applied to the Hutton TLP operated in the Hutton field in the North Sea and a certain variant of the design using the TLP Rule Case Committee type improved strength models. System failure probability and corresponding system reliability indices are derived for a more economical and efficient design. The redundancy characteristics are also addressed. The TLP forms are shown to possess high reserve strength and system safety.