Stress calculation of buried pipelines affected by typical geological hazards

Geological hazard is one of the main reasons for the failure of buried oil and gas pipelines. Particularly, the landslide, ground subsidence and surface collapse seriously threaten the safe operation of pipelines. Based on the existing research, several common models for analysis of pipeline-soil coupling were introduced, and the stress calculation methods of buried pipeline under the action of geological hazards were summarized. By means of experimental simulation and numerical simulation, the pipeline-soil interaction experiments and FLAC 3D numerical simulation were conducted under the action of different geological hazards such as collapse, settlement and landslide, and thus the stress distribution of pipeline under 3 types of geological hazards were obtained. By comparing the experimental results, numerical simulation results and the calculation results based on the theoretical model of pipeline, it can be concluded that it is feasible to simulate the pipeline-soil interaction with the finite difference software FLAC 3D, and for the theoretical calculation results only considering the pipeline, transportation medium and soil gravity load are quite different from the experimental and numerical simulation results, the influence of such parameters as soil friction and cohesion should be considered to improve the stress calculation method of pipeline.