落石冲击载荷下埋地油气管道力学分析

落石冲击会对埋地油气管道造成巨大损害,严重影响管道安全运营。利用有限元软件,建立落石冲击埋地油气管道的数值计算模型,模拟了落石冲击埋地管道的过程。通过改变落石冲击速度、管道壁厚及管道埋深参数,分析了相关参数变化时管道的力学变化规律,得到以下结论:埋地管道会在落石的冲击作用下形成凹陷,管壁应力迅速增大,管壁屈曲后应变迅速增大;管道应力、应变以及凹陷顶点的速度极值点会随着落石速度的增大而增大,随着管道壁厚、管道埋深的增大而减小;管道屈曲时,其应力会发生波动,同时应变增加更明显,凹陷顶点速度会有二次回升现象。研究结果对管道的安全运营具有一定的指导意义。

Mechanical Analysis of Buried Oil and Gas Pipeline under Rock Fall Impact

Rock fall impact could cause huge damage to buried oil and gas pipelines,which will seriously affect the safe operation of pipelines. Using the finite element software,the numerical calculation model of the rock fall impacted oil and gas pipeline was established to simulate the impacting process of rock fall on the buried pipeline. By changing the rock fall impact velocity,pipe wall thickness and pipe buried depth,the mechanical behavior of the pipeline was analyzed. The following conclusions are drawn: a dent was observed on the buried pipe under the impact of the rock fall,and the pipe wall stress increases rapidly. After the buckling of the pipe wall,the strain increases rapidly. In general,the pipe stress,strain and the velocity extreme point of the bent apex increase with the increase of the rock falling speed,and decrease with the increase of the pipe wall thickness and the pipe buried depth. When the pipe is buckling,the pipe stress will fluctuate,the strain will increase more significantly,and the bent apex velocity will have a second rise. The study could provide guidance for the safe operation of pipelines.