Application of Fuzzy Logic Methods to Evaluate the Serviceability of Northern Main Pipelines

Abstract

The paper presents the influence of climatic conditions of the North on the serviceability of trunk pipelines (TP) of the North, including: thermokarst, swelling, soil erosion, solifluction, bogging, presence of underground ice, ice formation and related negative processes. Such influences lead to the fact that in severe climatic conditions the pipeline transport is exposed to various deformations to a much greater extent and higher requirements should be imposed on materials, structures and laying technologies.
More than 65% of the trunk pipelines (TP) in the North are laid through swamps, watered areas and permafrost soils. The annual amplitude of air temperature fluctuations in these areas ranges from 80 to 90 degrees. This leads to unpredictable changes in spatial displacement and deformations of pipeline networks, reducing the reliability and safety of technical systems by 2-3.5 times. The problem of increasing the reliability and safety of TP is especially relevant for the northern regions, where, at extremely cold temperatures in winter, gas is one of the main sources of energy for heat supply systems. To improve reliability and reduce damage from the possibility of emergency situations, it is necessary to determine the risk components, identify vulnerabilities, determine the main parameters for developing measures to reduce the risk, mitigate the material and financial consequences in the event of an emergency. Due to the large number of uncertainties in the long-term data used, it is proposed to solve this extremely complex but necessary task using fuzzy models combining qualitative expert knowledge and quantitative statistical methods.