摘要海洋领域的蓬勃发展使得自升式海洋平台得到了广泛的应用，但是碰撞事故却一直威胁着自升式海洋平台的结构安全，一旦出现事故，就会造成难以预计的经济损失，严重的则会引起重大的环境污染。自升式海洋平台的破坏往往是在桩腿结构的管及管节点处产生，随后向周围扩展蔓延，直至整个平台崩塌。而K型管节点是常见的管节点类型，因此本文将针对深海自升式海洋平台K型管节点的碰撞性能进行分析研究。61810

本文开展了K型管节点落锤冲击试验，观察了K型管节点试件的变形损伤情况；在此基础上，分析推导出了K型管节点能量耗散的解析表达式；基于ABAQUS软件对K型管节点的冲击试验进行了仿真分析，将数值仿真的结果和试验结果进行对比，验证了数值仿真的可靠性，与此同时，将数值仿真结果和解析结果进行比较，验证解析方法的准确性。主要的研究内容和结论如下:

（1）开展了海洋平台K型管节点落锤冲击试验方案设计，进行了K型管节点落锤冲击试验，得到了碰撞力、塑性变形量等参数，为后续仿真和解析计算的分析验证提供了基础。

（2）基于塑性力学理论，结合K型管节点的试验结果，推导得到了K型管节点能量耗散的解析表达。

（3）基于K型管节点落锤冲击试验，利用有限元软件ABAQUS进行了数值仿真分析，分析了碰撞过程中的K型管节点的变形机理，并探究了不同冲击高度下的K管结构响应的规律。

（4）将数值仿真结果与试验结果进行了对比分析，进一步验证了数值仿真分析技术的可靠性；同时，将解析计算结果和数值仿真结果进行了比较，确定了解析修正方法，验证了解析方法的可靠性。

毕业论文关键词：自升式海洋平台；K型管节点；落锤冲击试验；解析方法；数值仿真

Abstract The jack-up platform has been widely applied due to the vigorous development of the marine areas, while collision has always been threatening the safety of jack-up platform structure, once the platform accident occurs, unpredictable economic losses will be caused, even serious environmental pollution. The destruction of the jack-up platform often starts at the tubular and tubular joints of notched structure, and spreads to the surrounding, until the whole platform collapses. And tubular K joints is common in jack-up platform, so the collision performance of tubular K joints at the deep-sea jack-up platform will be studied and analyzed in this paper.

In this paper, tubular K joints drop test has been carried out and the damage deformation of tubular K joint specimen has been observed. Based on this, the analytical expressions of tubular K joints energy dissipation have been derived. Then the finite element software ABAQUS has been used to simulate tubular K joints drop test, and the contrast between numerical simulation results and test results has verified the reliability of numerical simulation. In the meantime, comparison between numerical simulation results and analytical results has verified the accuracy of analytical method. The main research work and conclusions are as follows:

(1)The scheme of tubular K joint drop test has been designed. And tubular K joint drop test has been conducted to obtain parameters such as impact force, plastic deformation and so on, which has provided basis for subsequent simulation and the analysis and verification of analytic calculation.

(2)Based on the plastic mechanics theory, combined with tubular K joint test, the analytical expressions of tubular K joint energy dissipation have been derived.

(3)On the basis of tubular K joint drop test, finite element software ABAQUS has been used to conduct numerical simulation. The deformation mechanism of tubular K joint during the collision has been analyzed and the rules showing the influence of impact height on structural dynamic response have been explored.