Mechanical Properties of Buried Continuous Steel Pipe Under Reverse Fault

The purpose of this paper is to investigate the mechanical behavior of the buried steel pipeline in clay subjected to the reverse fault movement based on three-dimensional nonlinear finite element simulation of the soil-pipe interaction system. Based on the numerical study of the influences of different fault dip angles and internal pressures and pipe diameter-thickness ratios on the behavior of the pipeline, three typical failure modes: tensile failure of pipeline, local buckling and excessive deformation of cross section were identified and the corresponding critical reverse fault displacements were obtained in this study. The numerical results show that when the fault dip angle is 75°, the pipeline suffer local buckling failure with the smallest reverse fault movement, indicating that 75° is the most unfavorable dip angle. Moreover, large internal pressure can effectively reduce the excessive cross-sectional deformation of the pipeline. With the increase of internal pressure, the critical failure mode of the pipeline changes from local buckling to tensile failure of the pipeline. Finally, increase of the diameter-thickness ratio of the pipeline can significantly improve the performance of the pipeline subjected to reverse fault movement.