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Abstract

Ringing involves excitation of transient structural deflections at (or close to) structural frequency arising at the third-harmonic of incident wave field. Ringing waves are highly nonlinear containing strongly asymmetric transient waves and hence the shape of such waves becomes critical. This study develops mathematical formulation of impact waves responsible for ringing and examines their influence on offshore tension leg platforms (TLPs) with different geometric configurations located at different water depths. Based on the numerical studies conducted, it is found that the ringing response seen in pitch degree-of-freedom poses threat to platform stability. Also, undesirable response seen in stiff degree-of-freedom, like heave, emphasizes the necessity of the study for offshore compliant structures in deep waters, in particular.

Keywords

asymmetric waves offshore compliant structures tension leg platforms

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Ringing Response of Offshore Compliant Structures

Abstract

Keywords

References