滑坡作用下X80腐蚀管道的极限宽度分析

Limit width analysis of X80 corroded pipeline pass through landslide

针对X80腐蚀管道横穿滑坡时所涉及的安全预警问题,提出将极限宽度作为管道安全状态的判别因子,根据具体滑坡工况建立有限元模型,分析管道不同腐蚀尺寸和空间位置对腐蚀管道的力学行为与极限宽度的影响。结果表明:极限宽度可用于管道安全状态的评判;腐蚀的宽度和深度与管道极限宽度呈负相关,且对于腐蚀深度表现出高敏感性;内腐蚀对于管道安全状态的影响大于外腐蚀;坡度为30°的土质滑坡下,外径10.16 cm的无腐蚀X80管道的临界横穿滑坡宽度为21.2 m,含腐蚀管道横穿滑坡时的临界腐蚀深度为0.25倍的壁厚;腐蚀管道距滑坡区中部的距离大于6 m时对管道的极限宽度影响可忽略;管道应力与极限宽度呈负相关,腐蚀深度为0.2倍壁厚时管道最大应力始终在腐蚀处,其余位置的应力与无腐蚀管道一致。

In view of the safety early warning problems involved in X80 corroded pipeline crossing landslide,it is proposed to take the limit width as the discrimination factor of pipeline safety state,establish a finite element model according to the specific landslide conditions,to analyze the influence of different corrosion sizes and spatial positions of pipeline on the mechanical behavior and limit width of corroded pipeline.The results show that the limit width can be used to evaluate the safety state of pipeline.The width and depth of corrosion are negatively correlated with the ultimate width of pipeline,and show high sensitivity to corrosion depth;the influence of internal corrosion on pipeline safety is greater than that of external corrosion;under the soil landslide with a slope of 30°,the critical cross landslide width of the non-corrosive X80 pipeline with an outer diameter of 10.16 cm is 21.2 m,and the critical corrosion depth of the corrosive pipeline crossing the landslide is 0.25 times the wall thickness;when the distance between the corroded pipeline and the middle of the landslide area is greater than 6 m,the influence on the limit width of the pipeline can be ignored;the pipeline stress is negatively correlated with the limit width.When the corrosion depth is 0.2 times the wall thickness,the maximum stress of the pipeline is always at the corrosion position,and the stress at other positions is consistent with that of the non-corrosive pipeline.