典型地质灾害下埋地管道的应力计算

地质灾害是导致埋地油气管道破坏失效的主要原因之一,特别是管道沿线的山体滑坡、地层沉降及地面塌陷等严重威胁着管道的安全运行。基于已有研究,介绍了几种分析管土耦合作用的常用模型,总结了地质灾害作用下埋地管道应力计算方法。采用实验模拟与数值模拟相结合的手段,开展了塌陷、沉降以及滑坡地质灾害下管土相互作用实验以及FLAC 3D数值模拟,分别得到了3种地质灾害下的管道应力分布情况,通过比较实验结果、数值模拟结果以及管道理论模型计算结果可得:采用有限差分软件FLAC 3D开展管土相互作用模拟是可行的;仅考虑管道、输送介质以及土体重力载荷得到的理论计算结果与实验及数值模拟的结果相差很大,需要考虑土体摩擦力以及黏聚力等参数的影响,对管道应力计算方法进行改进。

Stress calculation of buried pipelines affected by typical geological hazards

Geological hazard is one of the main reasons for the failure of buried oil and gas pipelines. Particularly, the landslide, ground subsidence and surface collapse seriously threaten the safe operation of pipelines. Based on the existing research, several common models for analysis of pipeline-soil coupling were introduced, and the stress calculation methods of buried pipeline under the action of geological hazards were summarized. By means of experimental simulation and numerical simulation, the pipeline-soil interaction experiments and FLAC 3 D numerical simulation were conducted under the action of different geological hazards such as collapse, settlement and landslide, and thus the stress distribution of pipeline under 3 types of geological hazards were obtained. By comparing the experimental results, numerical simulation results and the calculation results based on the theoretical model of pipeline, it can be concluded that it is feasible to simulate the pipeline-soil interaction with the finite difference software FLAC 3 D, and for the theoretical calculation results only considering the pipeline, transportation medium and soil gravity load are quite different from the experimental and numerical simulation results, the influence of such parameters as soil friction and cohesion should be considered to improve the stress calculation method of pipeline.