Experience in the operation of pipelines in Siberia has shown the effectiveness of the use of free above ground pipelining on peat and moss-vegetation cover of permafrost soils as a natural base. Free laying is created at the expense of compensatory sections, it can be laid in an embankment of peat (ballasting is excluded), or on the surface in thermal insulation (a private solution for ground laying in an embankment, the amount of earthwork is minimized). At the moment, there is no regulatory framework in Russia for the design, construction and operation of free-laying surface pipelines in the area of frozen ground. The strength interaction of such pipelines with peat soil has been studied; there are methods for calculating the stress-strain state of a pipeline at the transition through the boundary between different soils, and methods for calculating settlement. However, when designing pipelines on frozen soils, it is necessary to take into account all the factors that affect the temperature regime of soils, as well as forecast changes in permafrost and soil conditions due to the construction development of the territory.
The method of above ground pipelining by self-immersion from the surface into frozen massif according the thermal effect of a pipeline on frozen soil is proposed. This method makes it possible to stabilize the position of the axis of the pipeline, to prevent progressive thawing of the soil, and to protect against pinching of the pipeline during freezing and heaving of the soil. A stable state is achieved as a result of the gradual and fading self-immersion of the pipeline to the bearing base. The results of experiments are graphically illustrated, which showed a pronounced redistribution of heat flows along the perimeter of the pipeline during the change of winter and summer regimes, which indicates the effectiveness of the regulation of heat exchange between the pipeline and permafrost. The thermal regimes of each month differed significantly from each other. Therefore, unlike conventional pipelines, which are calculated for the "worst" case, the calculation of pipelines in permafrost should be carried out taking into account the zero annual heat turnover by months of the year, which will limit the thawing halos under the pipeline and improve its performance.
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