Abstract: In order to ensure the stable operation of pipelines under landslide debris flow disasters, a strain analysis model for buried pipelines under the longitudinal action of landslide debris was established based on the thermal elastic-plastic theory. Meanwhile, the axial strain distribution characteristics were studied for buried pipelines under different lengths, widths and thicknesses of landslide debris flow. The results show that the influence degree of landslide debris flow size on the pipeline axial tensile and compressive strain is landslide thickness, length and width. By analyzing the influence of structural parameters such as diameter to thickness ratio, pipe wall thinning and pipe buried depth on axial tensile strain, it was found that the maximum axial tensile and compressive strain of the pipeline decreases significantly with the increase of slope and buried depth. The wall thickness reduction of the pipeline was positively correlated with the axial tensile and compressive strain of the pipeline, while the buried depth of the pipeline was negatively correlated with it. From the perspective of the influence of pipeline structural parameters on the maximum axial tensile and compressive strain of the pipeline, the order was pipeline buried depth, pipe wall thinning, and diameter thickness ratio. Properly increasing the buried depth of pipelines under the condition of landslide debris flow can reduce.

Key words: strain analysis model of buried pipeline;axial tension and compression strain distribution, influence law of axial strain, landslide debris flow hazard action risk