Keyword: «underground main pipelines»

Main pipelines are subjected to various exogenous processes in the permafrost area. The behavior of underground pipelines in permafrost soils is one of the main factors that affect their reliability. Frost heaving is one of the most dangerous processes that recur annually and can lead to pipeline bends in the vertical plane, sagging of individual sections, displacement, or loss of longitudinal stability. The article shows that the long-term monitoring of the planned-high-altitude position of the main gas pipeline revealed a section of the shore slope on the Khatasskaya channel of the river Lena, where intense deformations occur twice a year. The survey procedure is presented, and the graphs of their positions are provided. The changes in the planned-high-altitude position of the pipeline reach one meter. Thus, our hy-pothesis is confirmed.

The main pipelines laid on the territory of Yakutia are subject to faster wear due to the influence of permafrost soils on their operational reliability. The article shows that long-term monitoring of the planned altitude position of the main gas pipeline has identified a section of the coastal slope on the Tabaginskaya bayou, in which intense deformations occur twice a year. A mechanism is proposed that leads to complex deformations of the underground pipeline during frost heaving at the moment of the beginning of freezing of the soil. The developed mathematical model confirms this mechanism in the first approximation.