EPS 垫层对落石区油气管道的防护效果

中国石油天然气管道工程有限公司

管道;EPS 垫层;崩塌;落石;冲击响应

Protective effect of EPS cushion on oil and gas pipelines in rockfall areas
WANG Dongyuan, LI Chao, WANG Hongbo, YU Zhifeng

China Petroleum Pipeline Engineering Co. Ltd.

pipelines, EPS cushion, collapse, rockfall, impact response

DOI: 10.6047/j.issn.1000-8241.2019.12.017

备注

为了指导落石区油气管道 EPS 垫层的设置,对浅埋以及考虑崩塌落石冲击作用下油气管道的 减荷、耗能缓冲问题进行研究,通过有限元动力学软件 ANSYS/LS-DYNA 模拟不同厚度和初始密 度状态下聚苯乙烯泡沫塑料(EPS)垫层的耗能隔振效果,在落石冲击荷载作用下,EPS 垫层对冲击 能量的耗能隔振效应显著。通过对比未设置 EPS 垫层和设置 EPS 垫层管道的有效应力时程曲线发现,在相同条件下设置 EPS 垫层的耗能隔振效果是未设置 EPS 垫层的 5~7 倍。通过进一步研究 EPS 垫层得到以下结论:①采用较低密度的 EPS 垫层可以有效减小埋地管道的峰值有效应力,在实 际工程中选用低密度的 EPS 垫层是较优选择;② EPS 垫层的厚度与其耗能隔振效应并不成简单的 正比关系,随着厚度的增加,埋地管道峰值有效应力呈现出先减小后增大的规律;③埋地管道上覆 EPS 垫层厚度应该根据管道的实际覆土深度以及柔性填料的模量确定。(图 9,表 1,参 26)

In this paper, the load reduction and energy dissipation buffer were studied for pipelines which are buried in shallow depth or impacted by rockfall. Then, the energy dissipation isolation effects of the EPS cushion with different thicknesses and initial densities were simulated by ANSYS/LS-DYNA. It is shown that under the impact load of rockfall, EPS cushion has a significant effect on the energy dissipation isolation of impact energy. It is indicated by comparing the effective stress-time curve of the pipeline without EPS cushion and that with EPS cushion that the energy dissipation isolation effect of EPS cushion can reach about 5-7 times under the same conditions. And the following results were obtained by conducting further study on EPS cushion. First, lower-density EPS cushion can effectively reduce the peak effective stress of buried pipelines, and the application of low density EPS cushion in practical engineering is a superior choice. Second, the thickness of the EPS cushion is not in a simple proportional relationship with the energy dissipation isolation effect. As the thickness increases, the peak effective stress of the buried pipeline decreases firstly and then increases. Third, the thickness of the EPS cushion on buried pipelines shall be determined based on the actual soil depth of the pipeline and the modulus of the flexible filler. (9 Figures, 1 Table, 26 References)

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