Failure analysis and safety evaluation of buried pipeline due to deflection of landslide process

This paper focuses on the failure mechanisms of buried X65 pipeline due to non-uniform deflection of landslide process. First, fractographic tests are performed to analyze the failure causes of two typical accidents arising from landslide. Second, based on the non-linear stabilization algorithm, an improved finite element model is established to predict the load-bearing ability of buried pipelines under deflection load, and the nonlinear contact interaction between the pipeline and soil is considered. Particularly, effects of the surrounding soil, internal pressure and pipeline geometry are comprehensively investigated for the risk assessment of buried pipeline under large deflection. Finally, a strength failure criterion based on the maximum principal strain is proposed to determine the safe properties of buried pipeline under this special failure issue. Research in this paper can provide technical support for the safety assessment and standard formulation of buried pipelines.