深海悬链线管中管的载荷传递特性及接触作用机理研究

连续油管在深海油气工程中具有重要作用，但是因为其刚度小，在下入或作业 时难以承受轴向载荷易发生屈曲现象。特别是随着深海油气的开发，连续油管下入深海钢悬 链线立管的屈曲问题就越发凸显，甚至引发作业事故，成为制约该项技术推广应用的主要瓶 颈。这种典型管中管问题的研究具有重要意义，在国际上属于前沿领域。本项目的研究内容 为：(1)以悬链线浮动边界下的连续油管为研究对象，采用非线性静力学分析法探究临界载 荷、应力和应变的演变机制，揭示细长柔性杆在悬链线边界下的载荷传递规律；(2)引入波 浪、海流等干扰的分级等效载荷，采用有限元法提出接触作用算法，探究细长管中管在浮动 边界下的接触作用机理；(3)开展实验研究，运用最优化理论优化悬链线浮动边界下的细长 柔性杆屈曲接触力学模型。通过本项目的研究，有望为连续油管在深海钢悬链线立管中的应 用奠定理论基础，补充和完善现有管柱力学理论。

Coiled tubing has an important role in deep-sea oil and gas projects, but it is prone to occur buckling phenomenon in operating process because of its small stiffness. Especially with the development of deep-sea oil and gas, the buckling of coiled tubing into the deep sea steel catenary riser is more prominent, and it even leades to job accidents. So it becomes a major bottleneck restricting on the technology promotion and application. The typical pipe in pipe problem has great significance, and it belongs to the frontier in the international. This project as follows: (1) The project uses non-linear statics analysis to explore the evolution mechanism of the coiled tubing's critical load, stress and strain under the catenary floating boundary, reveals slender flexible rod load transfer law; (2) Through introduction of the equivalent load about the waves, currents and other interference, it proposes contact interaction algorithm with the finite element method, explores the contact mechanism of the slender pipe-in-pipe in floating boundary;(3) It carry out the experimental study, optimizes the buckling and contact model of the slender tube with optimization theory in floating boundary. It expects to establish theoretical basis of the coiled tubing's application in the deep-sea steel catenary riser through this project, and it will supplement and perfect the theory of existing pipe string mechanics.