自升式海洋平台升降作业刚柔耦合动力学特性

考虑桩腿柔性对自升式海洋平台升降作业的影响，系统开展平台整体升降动力学研究。针对桁架式和壳体式桩腿两种类型平台分别建立其刚柔耦合虚拟样机，在考虑各阶模态对结构动力响应影响权重基础上，采用DC增益模态截断法研究模型简化方法。研究齿轮齿条接触动力响应及各齿轮间载荷特征时变规律，揭示平台动力性能对桩腿柔性的敏感程度，进一步集成升降控制、监测系统搭建平台升降实验系统，开展穿刺应急工况平台升降动力性能实验验证研究。研究结果表明：刚柔耦合简化模型在确保分析精度基础上可有效提高计算效率，且能准确反映应急升降工况下平台动力学特性；桩腿柔性影响不同升降位置齿轮齿条接触力时变规律及载荷分配差异性，且对壳体式桩腿的影响程度要高于桁架式桩腿。

Rigid-flexible coupling dynamic characteristics for elevating operation of jack-up offshore platform

Considering the impact of leg flexibility on the elevating operation of jack-up platform, this study systematically performs a dynamic analysis of the overall platform. The rigid-flexible coupling virtual prototype is established for the truss-type and shell-type leg platforms. Considering the influence weight of each order of mode on the dynamic response of the structure, the model is simplified using the DC-gain mode truncation method. The contact dynamic response and the load variation characteristics over time of each gear are analyzed to reveal the sensitivity degree of the dynamic performance of platform to leg flexibility, so as to further integrate the elevating control and monitoring system to build the elevating test system of platform, and also carry out the experimental validation research on the elevating dynamic performance of platform under punch-through emergency conditions. The results show that the rigid-flexible simplified model can improve the computation efficiency effectively based on guaranteeing analysis precision, able to exactly reflect the dynamic property of platform in emergency elevating conditions. The flexibility of leg has an immediate impact on time-variation law of gear-rack contact force and the difference of load distribution at various elevating locations, and the influence on shell-type leg is higher than that on truss-type leg.