Abstract: The non-uniform settlement of the stratum is one of the common geological disasters faced by buried pipes, which affects the safe operation of pipes. The pipe soil coupling model in the stratum settlement area is established to investigate the effects of stratum settlement, pipe wall thickness, internal pressure, and pipe steel grade on the pipe’s buckling mode and mechanical properties. The results show that the axial tensile strain and compressive strain of the pipe are concentrated in the settlement transition zone under the action of stratum settlement. When the settlement is small, the surface strain of the pipe is wavy, while the pipe produces local buckling when the settlement is large. Under the same working conditions, thin-walled pipes are prone to buckling failure, whereas thick-walled pipes appear corrugated strain distribution. Additionally, with the increasing of internal pressure, the buckling of the pipe gradually weakens. The buckling degree of high-grade steel pipes is smaller.

Key words: stratum settlement, X80 pipe, axial strain, buckling failure