【作者】 景国泉；

【导师】 沈士明；

【作者基本信息】 南京工业大学 ， 化工过程机械， 2003， 硕士

【副题名】西气东输南京市城市天然气利用工程

【摘要】 埋地管道被广泛用来输送油、气等流体，相对于地上的普通管道其受力状态更加复杂，故埋地管道的安全性十分重要，一旦发生破坏，后果将很严重，因此有必要对埋地管道进行极限载荷研究与风险评价。 本文主要针对南京市城市天然气利用工程的埋地管道，研究其在不同地基性质、支座包角和地面载荷情况下的极限载荷，并进行了试验研究，同时进行了风险评价，主要研究内容与结论如下： (1)通过有限元计算分析，研究了不同地基性质、支座包角和地面载荷对埋地管道极限载荷的影响。结果表明地基性质和支座包角对极限载荷影响较小，硬基时，当地面载荷增加到一定值后，埋地管道的极限内压则迅速减小，软基时，地面载荷对埋地管道的极限内压的影响不大。 (2)本文设计了埋地管道的试验装置及系统，成功地进行了埋地管道的极限载荷试验研究，试验结果与有限元计算结果比较表明，两者的结果基本吻合。 (3)进行了含局部减薄缺陷埋地管道的有限元分析，表明其极限载荷低于用标准《含缺陷压力容器安全评定》推荐的地上管道评定方法的计算结果。 (4)本文在W.Kent Muhlbauer的评分法基础上建立了一种适用于埋地输气管道的风险评价方法，并对南京市城市天然气利用工程高压管线进行了风险评价，结果表明其相对风险较小，比较安全，但仍应进一步加强防范措施，确保其安全、稳定、长期的运行。更多还原

【Abstract】 A buried piping is widely used to transport oil, gas and so on. The loading state of piping is more complicated than normal piping, therefore the safety of buried piping is very important. The consequence will be very serious if a buried piping is failure, so it is necessary to study limit load of buried piping and to perform risk assessment of buried piping.In this paper, the limit load of buried pipe, that is used in Nanjing city nature gas using engineering, was studied by finite element analysis under various groundsill character, pedestal angle and ground pressure, and the risk assessment for this piping was performed. The limit load of buried pipe was measured by experiments. The research contents and results were as follows:(1) With FEA method, the effects of various groundsill character, pedestal angle and ground pressure on the limit load of buried pipe were studied. The results show that the effects of groundsill character and pedestal angle on the limit load are little. The effect of ground pressure on the limit load is also little when the groundsill is flexible, but when the groundsill is rigid, the limit load of buried pipe is decreases rapidly as the ground pressure increases to a certain value.(2) The experimental equipment and system of buried pipe were designed, and the experiment of buried pipe was carried out successfully. The results of experiment and FEA are almost equal.(3) The limit load of buried pipe containing a local wall-thinning was studied by FEA. Calculative results of limit load by FEA is less than that calculated by normal pipe assessment method which is recommended by criterion-Safety Assessment for Pressure Vessels Containing Defects.(4) The risk assessment method of natural gas buried pipeline based on W.Kent Muhlbauer’s method was improved. Then the risk of high pressure pipeline used for Nanjing city natural gas engineering was assessed. The assessment results show that the risk of this pipeline is low, and the pipeline is safe, but some measures should be adopted in keeping safety and stability of pipeline.更多还原