斜拉索管道跨越结构清管动力响应分析

【作者】 许萍；

【导师】 李长俊； 廖柯熹；

【作者基本信息】 西南石油学院 ， 油气储运工程， 2003， 硕士

【摘要】 本文在参考各种管道跨越结构的静力平衡分析和斜拉公路桥的动力特性分析基础上，根据流体诱发圆柱结构振动理论，采用有限单元法对具有立式补偿器的斜拉索管道跨越结构清管时的动力响应进行分析。 本文以大中型斜拉索管道跨越结构为研究对象，将输送管道视为连续弹性梁，考虑清管时积液在边跨中满管流动引起的耦合振动，建立了斜拉索管道跨越结构的有限元分析模型。 首先根据Hamilton原理，推导了边跨中积液满管流动的固液耦合振动方程；然后利用有限元理论得出整体结构动力平衡方程，使用Newmark法计算在各种清管工况条件下跨越结构的动力响应。文中针对斜拉索非线性特性提出了线性化处理方法，同时考虑了结构参数、斜拉索的垂度及边界条件等对结构自振频率和振型的影响。 本文使用ANSYS分析软件编写了计算程序，通过对有限元模型进行分析计算，得出在各种清管工况条件下，当清管器及积液通过管道跨越结构时，管道振动的位移及应力等数据；然后应用相关规范的强度理论对管道及斜拉索进行强度校核，得出在一定的清管速度下，管道与斜拉索强度安全范围内的最大允许积液长度，及在此极限状态下跨越结构的最大振动位移。 涪江输气管道跨越是典型的斜拉索管道跨越结构，四川石油勘察设计研究院对涪江跨越清管时的动力特性作了现场测试，本文利用现场测试所得参数与文中计算结果作了对比分析，以验证计算结果的准确性。更多还原

【Abstract】 In this paper, analyses for static equilibria of various aerial crossing pipeline structures and dynamic characteristics of cable-stayed bridges are referenced. According to the fluid-induced vibration of cylindrical structure theory, the finite element method is adopted to analyze dynamic response of the aerial crossing pipeline structure supported by inclined cables with vertical expansion joint during the pigging process.The large-scale aerial crossing pipeline structure supported by inclined cables is investigated in the paper. The conveying pipeline is supposed to be a continuous elastic beam, and a finite element analysis model is built considering fluid-solid coupling vibration induced by liquid accumulation filled in the side span during the pigging process.At first, following the Hamilton principle, the fluid-solid coupling vibration equation is established on the side span, in which liquid accumulation is brimming and flows. Then the finite element theory is used to formulate dynamic equations of the whole structure, and the Newmark method is used to calculate dynamic response of the aeria crossing pipeline structure during different pigging processes. This paper presents a linear method for nonlinear behavior of inclined cables. Structure parameters, cable sags and boundary conditions affecting on the structure’s natural vibration frequency and vibration modes are given.With a computational program wrote by the ANSYS software, the finite element model is analyzed and calculated in the paper, and the stresses and the vibration displacements of the pipeline are obtained during different pigging processes, when the pig and liquid accumulation pass the aerial crossing pipeline structure. Then the specified criterion of intensity theory is utilized to check the pipeline and inclined cables’ safety. Through the analysis, the maximum permissible length of liquid accumulation, which is in the extent of the pipeline and inclined cables’s security, is obtained at the definite pigging velocity, and the maximum vibration displacement of the structure is also obtained in that limit condition.The Fujiang gas crossing pipeline structure, which is a representative aerial crossing pipeline structure supported by inclined cables, has been tested on the spot for its dynamic characteristics during the pigging process by the Sichuan Petroleum Prospecting And Design Academy. The required parameters are compared to the calculated results of this paper to verify its accuracy.更多还原