地质灾害和管体缺陷是油气管道安全运行的两大风险，山体滑坡是长输油气管道常见的一种地质灾害，裂纹是管道运行中难以发现却时有发生的管体缺陷之一。当穿越滑坡区的管道遭遇管体裂纹时，多重载荷的作用可能导致管体裂纹加剧甚至断裂失效。基于极限分析设计准则，研究了相关因素对滑坡区管道轴向裂纹的影响，采用有限元法，分析了滑坡宽度、滑坡位移、裂纹位置、裂纹深度比、裂纹形状比以及管道内压对裂纹 J 积分的影响。结果表明：滑坡宽度越大，J 积分越小，滑坡位移越大，J 积分越大；裂纹处于 12 点位置时，其 J 积分值最大，即轴向裂纹垂直于滑坡面时最危险；裂纹深度比和管道内压的增加均会导致 J 积分最大值呈指数增加，而裂纹形状比的增加会导致 J 积分最大值呈线性减小，J 积分均在裂纹最深处取得最大值；较大的裂纹深度比会导致裂纹沿深度方向的扩展速度远大于沿长度方向，而较大的裂纹形状比会导致裂纹沿长度方向的扩展速度高于沿深度方向。
Geological disasters and pipeline defects are two major risks to safe operation of oil and gas pipelines. Mountain landslides are a common geological disaster in long-distance oil and gas pipelines. Cracks are one of the pipe defects that are difficult to be found but often occur in pipeline operation. When a pipeline pass-ing through the landslide area encounters pipe cracks， the effect of multiple loads may lead to the aggrava-tion of pipe cracks and even fracture failure. Based on the limit analysis design criterion， the influence of relevant factors on the axial crack of pipelines in the landslide area is studied. The influence of landslide width， landslide displacement， crack location， crack depth ratio， crack shape ratio and pipeline internal pres-sure on crack J integral is analyzed by the finite element method. Results showed： The greater the landslide width， the smaller the J integral， and the greater the land- slide displacement， the greater the J integral. When the crack is located at the 12 o’clock position， the J integral value is the largest， that is， the axial crack is the most dangerous when it is perpendicular to the landslide surface. The increase of crack depth ratio and pipe-line internal pressure will lead to an exponential increase in the maximum value of the J integral， while the increase of crack shape ratio will lead to a linear decrease in the maximum value of the J integral， and the maximum value of J inte- gral is obtained at the deepest part of the crack. A larger crack depth ratio will lead to crack propaga- tion velocity along the depth direction being much larger than that along the length direc-tion， and a larger crack shape ratio will lead to crack propagation velocity along the length direction being higher than that along the depth direction.