Large-Scale Physical Model Test on the Influence of Landslide Hazards on Oil and Gas Pipeline Bending

Due to its wide distribution, the long-distance oil and gas pipeline will inevitably pass through the landslide risk area. This study aims to investigate the impact of landslide geological disasters on oil and gas pipelines, particularly focusing on the deformation characteristics of pipelines under various landslide dip angles. To achieve this, a large physical simulation platform was designed and established as part of the methods used to replicate the effects of landslide geological disasters on oil and gas pipelines. Experiments were conducted at different dip angles, monitoring and analyzing changes in stress and strain within the pipeline, as well as soil displacement. Based on the experimental results, we draw the following conclusions: (1) the bending process of the pipeline can be divided into slow-bending stage, constant-speed bending stage, and accelerated-bending stage. (2) The tensile strain is produced back to the impact direction of landslide; the compressive strain is produced facing the direction of landslide. At the point with the largest impact force of the landslide, when the dip angle of the landslide is 38°, the rate of slow increase is the greatest in the four stages, which is about 77 times that at a slope of 10° (3) At the same point, with the increase of the dip angle, stress is also gradually increasing. When the slope reaches the angle posing a landslide hazard, the maximum rate of change of stress is about 26.9 × 10⁻⁶kPa/s. (4) At the centre of the pipeline, the strain difference between the back and facing the direction of the landslide increases continuously. These experimental results have obtained the pipeline deformation law in the whole process of pipeline landslide disaster, which can provide great help for the monitoring and early warning of pipeline landslide disasters on site.