Frost heaving and thaw collapsing disasters are the main causes that adversely influence pipe-line projects in permafrost regions, which also cause certain harms to safe operation of underground normal-temperature oil transportation pipelines,so enough attention should be paid in design and con-struction. By analyzing the reason of frost heaving formation and the harm on oil transportation pipe-lines caused by frost heaving disaster, combined with the practical experience of Mo-Da and Second Mo-Da Oil Transportation Pipeline through permafrost regions, along with the increase of oil trans-portation temperature, and faced with the influence of high oil temperature and new working condi-tion of paralleled laying on pipeline, effective frost heaving and thaw collapsing control measures are put forward. For frost heaving control, measures such as closure, drainage, increase of pipeline lay-ing depth, pipeline trench excavation and change of filling soil are adopted; for thaw collapsing con-trol, measures such as increase of pipe wall thickness, insulation laying, hot rod, overhead support of concrete pile and connecting beam, sawdust or ecological bag slope protection are adopted. At the same time, real-time monitoring of thaw collapsing condition is taken in permafrost regions, which can ensure safe and stable operation of oil transportation pipelines.%冻胀、融沉灾害是多年冻土区对管道工程产生不良影响的主要因素,对埋地常温输油管道的安全运行造成一定的危害,因此在设计施工中要引起足够重视.通过对冻融形成的原因及冻融灾害对输油管道产生的危害进行分析,结合中俄漠大线和漠大二线两条输油管道经过多年冻土区的实践经验,以及随着管道输油温度的提升,面临高油温、并行敷设新工况对管道带来的影响,提出了行之有效的冻融防治措施.对于冻胀防治采取截流、排导、增加管道埋深以及管沟开挖换填土措施,融沉防治采取增加管道壁厚、保温敷设、热棒、混凝土桩连系梁支撑架空、木屑或生态袋护坡措施,同时对多年冻土区管道融沉情况进行实时监测,以保证输油管道安全稳定运行.
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