中俄输油管道沿线多年冻土工程地质问题及防治对策

Study of the Engineering Geological Problems in Permafrost Region along China-Russia Oil Pipeline and Prevention Countermeasures

研究目的:中俄输油管道穿越我国东北大兴安岭多年冻土区,多年冻土的融沉及活动层的冻融对管道地基工程的破坏,将造成管基的不均匀变形,影响输油管道的安全。本文通过对中俄输油管道沿线多年冻土区工程地质问题进行分析研究,有针对性地提出用以保证输油管道工程安全稳定的防治对策。研究结论:(1)在多年冻土区采用架空方式敷设输油管道,可极大地避免不良工程地质问题对输油管道安全的影响;(2)冻融差异变形是导致冻土地区管道变形破坏以及诱发管道病害的主要原因,通过减小冻胀变形或融沉变形的绝对值来减缓管道在纵向方向差异变形上的剧烈程度均是输油管道克服变形破坏的有效途径;(3)在冻胀敏感性土和高含冰量多年冻土等不良工程地质地段,可采用管道保温、换填、管壁加厚等措施来消除或减弱管道轴向不均匀变形程度。

Research purposes： China - Russia oil pipeline crosses the permafrost region in Daxinganling of northeast China. The frost heaving and thawing settlement in permafrost region and active layer would destroy the oil pipeline engineering, resulting in uneven deformation of the pipeline foundation and influencing the pipeline security. This paper analyzes and studies the engineering geological problems in permafrost region along China - Russia oil pipeline, and puts forward the prevention countermeasures for ensuring the security and stability of the oil pipeline engineering. Research conclusions： （ 1 ） Installation of overhead oil pipeline in permafrost region can extremely reduce the influence of unfavorable engineering geology on the security of the oil pipeline. （2） The main reason for the pipeline＇s deformation damage and inducing disaster to the pipeline is the difference in freezing and thawing deformation in permafrost region. Therefore, reducing the absolute value of frost heave or thawing settlement deformation to slow down the acute degree of the pipeline＇s differential deformation in the vertical direction is an effective way to overcome the deformation damage （3） In the unfavorable geological area with expansive sensitive soil and ice - rich frozen soil, the measures of insulating the pipeline, replacement of filling and thickening the pipe wall can be taken for eliminating or reducing axially uneven deformation of the pipeline.