畸形波作用下半潜式平台的极限生存能力评估

摘要

极限海浪可能对海洋平台的安全造成极大的威胁，故合理地评估平台在此海况下的运动响应和系泊缆索的动张力响应对平台设计具有重要意义。文章首先利用新波理论和随机海浪理论建立了畸形波入射波模型。然后利用间接时域方法和非线性有限元法分别建立了平台主体运动和系泊缆索动力响应的求解方程，并根据导缆孔的平衡方程建立了平台主体和系泊缆索的时域耦合运动方程。最后深入分析了某半潜平台在畸形波作用下的运动响应和系泊缆索的动张力响应，对平台的极限生存能力进行了评估。%The extreme waves may be a great threat to the offshore platforms, so the accurate prediction of the motion and tension response under extreme waves is of great importance. In this paper, the incident freak wave model was constructed by the random wave theory and new wave theory. The dynamic equations of the floating offshore structures and mooring cables were established by the indirect time-domain method and non-linear finite element method, respectively. And, the coupled motion equation was built based on the‘equilibrium equations of fairlead points’. Finally, the coupled response of semi-submersible platform un-der freak waves was analyzed, and the extreme safety of the platform was evaluated.