以X80管线钢为研究对象,通过ABAQUS有限元分析软件建立了横向滑坡作用下的含腐蚀缺陷输气管道模型,研究了滑坡位移,管道内压,腐蚀缺陷的轴向位置、环向位置和缺陷深度等5个工程要素对X80管道应力的影响,并对管道进行了安全评价。结果表明:随着滑坡位移、管道内压和缺陷深度的增加,管道最大等效应力增大;缺陷轴向位置距离管道中心越远,最大等效应力越小,滑坡位移对管道等效应力的影响越大;当腐蚀缺陷处于不同的环向位置时,管道的最大等效应力也不同;当缺陷深度超过一定范围后,随管道内压的增大,缺陷深度对管道最大等效应力的影响超过内压的影响。仅采用基于应力的失效准则对滑坡区域内含缺陷管道进行失效压力评价不能完全确定管道是否安全,建议对管道缺陷处除采用基于应力的失效准则外,还应采用基于应变的失效准则进行二次评价。

X80 pipeline steel was taken as a research object, and the gas pipeline model with corrosion defects under the action of lateral landslide was established by ABAQUS finite element analysis software. The effects of the five engineering factors including landslide displacement, pipeline internal pressure, axial defect position, circumferential defect position and defect depth on the stress of X80 pipeline steel were studied. And safety assessment of the pipeline was conducted. The results show that with the increase of landslide displacement, pipeline internal pressure and defect depth, the maximum equivalent stress of pipeline increased. The farther the defect from the center of the pipeline was, the smaller the maximum equivalent stress was, and the greater the effect of landslide displacement on the maximum equivalent stress was. When defects were in different circumferential directions, the maximum equivalent stress of pipeline was also different. When the defect depth exceeded a certain range, with the increase of internal pressure, the effect of defect depth exceeded that of internal pipeline pressure on maximum equivalent stress of pipeline. Failure pressure evaluation of pipeline with defects in landslide area using stress-based failure criteria cannot completely determine whether the pipeline is safe or not. It is suggested to use stress-based failure criteria for pipeline defects, and use strain-based failure criteria for secondary evaluation.