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摘要在海洋能源勘探和开采的过程中，海洋平台起着不可替代的作用，尤以自升式平台占据着重要地位，是海洋油气探井、钻井和开采的主要作业基地之一，但是船舶碰撞导致的平台结构损坏一直是威胁海洋平台安全的主要因素。评估结构耐撞性能最可靠的方法是实尺度碰撞试验，然而对于平台的碰撞试验，因其耗资巨大而不易开展。因此，适当开展比例模型试验可以为简化解析算法及数值仿真计算提供验证依据，从而揭示平台结构在碰撞过程中的损伤变形机理，对更好的开展自升式平台碰撞结构设计具有重要意义。86622

本文首先运用量纲分析法推导了船舶-自升式海洋平台碰撞的动态相似率，进行碰撞结构缩尺修正方法研究；并基于有限元软件ABAQUS进行了数值验证，最后在局部模型碰撞的基础上，设计了平台整体碰撞模型试验方案，主要研究工作如下：

（1）以船舶与自升式海洋平台碰撞为背景，基于相似第二定律，运用量纲分析法推导管节点碰撞中的动态相似准则，结合有限元仿真技术，以平台桩腿典型直管和K管为研究对象，将自升式海洋平台碰撞场景进行简化，建立不同的缩尺比碰撞模型，通过不同缩尺比模型的动态结构响应特性验证相似理论的可行性。

（2）通过改变冲击速度来修正缩尺过程中由于应变率敏感性的存在而引起的误差。与传统量纲分析法中的选取长度、质量和时间作为基本量纲不同，本文以冲击速度、冲击质量和动态应力作为基本量纲，求得计及应变率敏感性的各物理量的相似关系，并且推导速度修正系数公式。

（3）对整体平台碰撞模型进行简化，分析出最佳平台模型简化方法并初步设计了整体平台碰撞模型和约束工装，简要提出试验方案。

关键词：自升式平台；量纲分析；缩尺模型；数值仿真；模型试验

Abstract In the process of offshore exploration and exploitation, the offshore platform plays an irreplaceable role。 For all kinds of offshore platforms, jack-up platform occupies an important position, for it is one of the main operating bases for exploring, drilling and mining offshore oil and gas。 However, ship collision has been one of the main factors threatening the platform, for the collision can cause serious damage to platform structures。   It is known that real scale collision tests are the most reliable method to evaluate collision resistance of structures。 The fact is that it is too expensive for collision tests of offshore platforms to carry out。 Therefore, the scale model tests are necessary and significant to provide basis for validating the analytical method and finite element method。 It is very important to do the crashworthiness design for offshore platforms and study the platform deformation mechanism during collision scenario。

In this paper, the dynamic similarity of the collision of the ship and jack-up platform is derived by using the dimensional analysis method。 Based on the finite element software ABAQUS, the overall impact model test scheme is designed on the basis of local model collision。 The main studies and conclusions are as follows:

(1) Based on the collision between the ship and the jack-up platform, the similarity of the second law, the dynamic similarity criterion is derived by using the dimensional analysis method to derive the dynamic similarity criteria in the collision of a pipe node。 Based on the finite element simulation technology, the model of the platform of the typical straight pipe and the K pipe is the research object Jack-up platform is simplified。 Different scale collision models are set up to verify the similarity theory of the feasibility of the different scale model of the dynamic structure response characteristics。