断层上覆土层破裂对埋地管道的影响

利用ANSYS程序建立的三维管土非线性有限元模型,计算分析了断层基岩上覆土层的变形破裂形式、土层厚度及土层土质的硬度对埋地管道的影响.结果表明,埋地管线发生大变形及失效的位置由上覆土层的破裂形式决定,穿越土层发生塑性变形及破裂区域的管段是管道发生塑性变形的管段.当断层倾角发生接近于90°的错动时,随上覆土层破裂的发展,埋地管道产生两处塑性变形区段.上覆土层越厚,埋地管道发生塑性变形的长度越长,变形值减小.埋在土质较硬土层中的管道发生塑性变形的管段长度短,极限应变值大.

Responses of Buried Pipeline Crossing Fault Due to the Overlaying Soil Rupture

The influences of the rupture mode,the overlaying soil thickness and stiffness to the buried pipeline is analyzed by a 3D soil-and-pipe nonlinear ANSYS finite element model.The numerical results show the soil rupture mode determines the locations of the pipeline large deformation or failure,and the pipeline plastic deformation occurs at the zone where the plastic deformation or rupture of the overlaying soil occurs.When the fault dislocation angle is near 90°,two plastically deforming pipeline sections appear with the overlying soil rupture extending.And the thicker the overlaying soil is,the longer the plastically deforming length of the buried pipeline is and the less its strain is.The plastically deforming pipeline length in the stiff soil got short,while its maximum strain increased.