Novel Computational Nonlinear Analysis of Soil-Pipe Interaction under Large Displacement in Geo-Hazard Environment: a Preliminary Study

尽管经过几十年的研究和开发，石油和天然气管道故障仍然不可避免。对管道力学应力和变形的新认识将有助于改进管道设计和施工，从而减少管道故障。我们关注地质灾害环境中管道的安全性，例如加拿大北方的深沼地，并决心了解阿尔伯塔最近的管道破裂。不稳定的土壤条件，如滑坡和地下水压力变化，在这些管道中产生过度的应力和变形，这可能比已知的结构完整性更危险。 该项目的新奇在于使用三维计算机模拟土壤-管道相互作用的大位移，这在管道设计中目前还没有进行，因为管道的大挠度、管道与周围土壤之间的大滑动以及土壤固结与地下水压力波动的分析非常具有挑战性。由于缺乏有效的分析工具，管道设计往往存在高风险或过于保守的问题。通过我们的案例研究，可以更好地理解管道的完整性，这些案例研究通过计算模拟了恶劣环境中的危险载荷和位移条件。 该项目与加拿大应力工程服务公司合作，将开发一种有效的工具，用于加强地质灾害环境中管道的安全设计，并在环境发生变化时对已安装管道进行安全评估。该工具将用于正在进行的加拿大管道项目，这将促进经济，但保护阿尔伯塔和加拿大的环境。

Despite decades of research and development, oil and gas pipeline failures are still inevitable. New understanding in the mechanical stress and deformation of the pipeline will help improve pipeline design and construction and therefore reduce pipeline failures. We are concerned with the safety of pipelines in geo-hazard environments such as deep muskegs in northern Canada, and are determined to understand the most recent pipeline rupture in Alberta. Unstable soil conditions, such as landslides and ground water pressure changes, produce excess stress and deflection in these pipelines, which may be more dangerous to the structural integrity than what is known. The novelty of this project is the use of three dimensional computer modelling of large displacement of the soil-pipe interaction, which is not currently performed in the pipeline design because the analysis is very challenging with large deflection of the pipe, large sliding between the pipe and soil surrounding it, and soil consolidation with ground water pressure fluctuations. Due to lack of effective analysis tools, pipelines are often designed with either high risk or over conservatively. The integrity of the pipelines will be better understood with our case studies that computationally simulate hazardous loading and displacement conditions in harsh environments. This project collaborating with Stress Engineering Services Canada will lead to the development of an effective tool for enhanced safety designs of pipelines in geo-hazard environments and for the safety assessment of installed pipelines when environmental changes occur. The tool will be used in the ongoing Canadian Pipeline projects, which will promote economy and yet protect the environment in Alberta and Canada.