DESIGN OF THE SUPPORT FOR UNDERGROUND PIPELINE FASTENING IN CONDITIONS OF INSULAR AND DISCONTINUOUS PERMAFROST ZONES

The relevance of the study is caused by the need to develop the effective technologies to ensure the preservation of the design position of the main pipeline sections in the areas with permafrost distribution. The work is of particular relevance, taking into account active development of the northern and Arctic gas and oil regions of Russia. The main aim of the research is to develop a design solution and the construction of underground supports for fixing non-heat-insulated sections of the pipeline in seasonally thawing and insular permafrost. Objects: main pipeline fixed in frozen soils. Results. The paper considers the existing types of supports and suspensions of pipelines in the context of their applicability for the fixing underground sections of oil and gas pipelines in permafrost and seasonally thawing soils, including at the intersection of insular permafrost, ice lenses and pingos. Based on the results of the analysis of the possible loads and limitations of existing supporting structures of pipelines with the risks of emersion and sagging of underground sections in the melted trench, the design of underground anchor supports is proposed and conclusions are made about the advantages of their use. To calculate the loads and determine the required dimensions and number of anchors, cross-sections of stretch ropes and a mounting clamp, a finite-element model was developed. Its effectiveness was confirmed analytically and experimentally on the developed test bench.