ОЦЕНКА ВЛИЯНИЯ ГЕОДИНАМИЧЕСКИХ ЗОН, ПЕРЕСЕКАЮЩИХ МАГИСТРАЛЬНЫЕ ГАЗОПРОВОДЫ, НА ИХ НАПРЯЖЕННО-ДЕФОРМИРОВАННОЕ СОСТОЯНИЕ

The relevance. One of the reasons capable of destroying gas pipelines is geodynamic effects, since with long-term operation of gas pipelines located, for example, on tectonic faults, the damaging factor due to bending stresses is accumulated. The analysis of the actual position of gas pipelines according to in-line technical diagnostics showed the presence of potentially dangerous areas, in which the curvature does not match the design, and therefore the bending stresses can also differ significantly in absolute magnitude in the larger direction from the design. Therefore, it is necessary to identify such potentially dangerous areas in a timely manner and, depending on the level of actual stresses, carry out restoration measures. The main aim of research is to analyze the influence of geodynamic zones crossing the main gas pipelines on their stress-strain state using the data from in-line inspection and taking into account their operation beyond the depreciation period. Objects: four thread corridor of the main gas pipeline running through the western Urals. Methods: analytical methods for the study of the stress-strain state of gas pipelines according to the data on the spatial position of its axis, obtained by the methods of the generally accepted technology and the data of the in-line technical diagnostics. Results. The authors have analyzed the main stages of the generally accepted technology for detecting geodynamic zones and determining its main parameters, the assessment of stress-strain state. The paper demonstrates the possibility of detecting potentially dangerous areas at intersections with geodynamic zones, according to the in-line technical diagnostics. It was established that with the increase of the gas pipeline service life, the number of potentially dangerous areas grows, in which the radius of curvature does not meet the requirements of regulatory documentation for the minimum allowable equal to 1000 D. Based on the results of the data processing of the in-line technical diagnostics, the examples of determining the values ​​of bending stresses exceeding the standard values ​​are given. As it is impossible to complete re-laying of gas pipeline, it is proposed to bring regulatory requirements for the level of stresses. In addition, the possibility of identifying active geodynamic zones and their parameters, according to the data of the in-line technical diagnostics, is shown.