Stress effect of the interface between buried pipeline and sandy soil layer in a cold environment

The interaction between buried pipe and soil is an important aspect of disaster prevention and mitigation. In this paper, interfacial stress tests between room-temperature or frozen sand and pipeline were performed to study the interfacial stress problems experienced by a buried pipeline in sand. According to the basic assumptions, a calculation model for the mechanical stress of the buried pipeline was established. The experimental data were used to verify the correctness of the theoretical calculation model and the stress–displacement formula of the buried pipeline interface was fitted. The stress–displacement curve of the interface between the pipe and the room-temperature soil was compared with the stress–displacement curve of the interface between the pipe and the frozen soil. The results show that the interfacial stress value calculated by the theoretical model of pipe–soil interfacial stress is consistent with experimental values. The stress at the pipe–soil interface after the sand was frozen is much larger than the stress at the pipe–soil interface when the sand is at room temperature. Frozen soil has a great influence on the pipe–soil interaction. This theoretical formula can be used to analyze the interfacial stress problem for the pipe–soil coupling and lay a foundation for further studies of the influence of the permafrost–pipeline interaction on the stress and strength of the pipeline. •The pipe–soil interactions of the buried pipeline in the nonfrozen and frozen sand layers were studied.•A calculation model for the mechanical stress of the buried pipeline was established.•The experimental data were used to verify the correctness of the theoretical calculation model.•The stress–displacement formula of the buried pipeline interface was fitted.•The established formula can be used to calculate the interfacial stress between the pipe and the soil.