滚石冲击作用下埋地高压输气管道的可靠性分析

地质灾害往往会对高压输气管线造成安全隐患,岩体崩塌引起的滚石冲击是导致埋地输气管道第三方破坏的主要破坏形式之一。通过概率分布求出滚石产生的偶然性载荷对管道的冲击频率,根据可靠性理论,用管线钢自身的强度和撞击产生的工作应力,建立强度应力的安全裕度方程。然后利用LS-DYNA有限元软件,建立滚石冲击管道模型,计算不同条件下埋地输气管道的最大应力Sm,确定Sm的分布规律。最后,根据应力和强度的分布求得管道可靠度指标和失效概率。本研究提供的方法和结论对埋地输气管道的风险评估、管道的设计及施工具有重要的参考价值。

Reliability analysis of buried high pressure gas pipeline under the impact of rock fall

The geological disasters often result in the destruction of high pressure buried gas pipeline. The rock fall caused by means of collapse is one of the major modes to lead to the failure or damage of the buried gas pipeline In this paper, the strike frequency of the impact by the rock fall was firstly figured out in terms of probability distribution. And then, based on reliability theory, the corresponding safety margin equations were educed by using the strength distribution of the gas pipeline and the working stress acting on the gas pipeline. The finite element model of high pressure buried gas pipeline Was established by using LS-DYNA and the maximum stress Sm of the buried pipeline were obtained under different conditions. After that, the distribution type of Sm could be determined and the corresponding reliability index and invalidation probability could be gotten. The methodology and conclusions in this paper may provide some references for the risk assessment, design and construction of buried gas pipeline.