The climatic factor of warming, which is evidenced by a significant number of scientists and research teams in Russia and the world, has a significant impact on the cryogenic state of permafrost soil, the preservation of which is one of the most common principles of construction in the North. The influence of projected climatic changes in planning up to 2050 on the efficiency of seasonal cooling devices, the principle of operation of which is based on seasonal soil freezing, is considered. The conducted modeling has shown that in a situation of stable climate, the preservation of the cryogenic state of permafrost soil is realized without the use of additional measures. With warming with a trend of 0.1 °C per year, seasonal cooling devices do not ensure the preservation of the current level of the cryogenic state of the soil and additional measures are required to increase their efficiency in the summer. In the case of more extreme warming with a rate of 0.25 °C per year, the modeling results show that seasonal cooling devices do not significantly affect the rate of soil thawing and the solution to the problem should be its complete replacement with systems with year-round action.
Construction of oil and gas infrastructure facilities on permafrost soils is the most important task of increasing the raw material base of the entire fuel and energy industry in Russia. Permafrost soil is a complex, multicomponent system, state of which depends on many factors. Buildings and structures built under such conditions, on the one hand, have a complex thermal effect on permafrost soils, and on the other hand, they perceive the consequences of changes in the characteristics of such soils. This situation leads to the fact that buildings and structures on permafrost soil during their life cycle are subject to complex and poorly predictable deformations. Article presents the results of a study for various degradation processes of permafrost soils that can be implemented at construction sites of industrial facilities. Analysis of the deformations causes for engineering structures at the gas industry in the permafrost zone is carried out. Series of reasons causing such deformations have been investigated. Comprehensive criterion for assessing changes in permafrost-geological conditions of industrial sites is proposed. It is suggested to apply the method of calculating the individual characteristics for the temperature regime of the territory to monitor and assess the conditions of heat exchange and predict changes in the geocryological conditions of permafrost soil.
Wide exploration and industrial exploitation of hydrocarbon fields in Yamal Peninsula pose in front of construction and mining companies critical problems of efficient construction at constantly evolving fields taking into account climatic and geocryological conditions of their location. Yamal Peninsula is characterized by unstable soils, the mobility of which has a substantial impact on the changes in spatial arrangement of field facilities, not only in the direct process of construction, but also during their scale-up and equipment overhaul. The paper examines implementation of 3D spatial arrangement modelling of industrial facilities into the process of construction and installation works at hydrocarbon fields in the northern construction-climatic zone. The purpose of implementing this method combined with 3D spatial modelling of equipment connections lies in reliability and safety enhancement of the facilities throughout their entire lifespan. Authors analyze statement and solution of the problem associated with alignment and installation of prefabricated equipment and pipelines, taking into account advanced technologies of 3D design and modelling. The study examines a 3D spatial model with the elements of equipment connection geometry; the model is related to existing production facilities at the field. Authors perform an analysis and in mathematical terms formulate the problem of optimal spatial arrangement for such models. The paper focuses on typical deviations, occurring in the installation process of constructions and connection facilities, their spatial arrangement is modelled. Possible solutions are offered, as well as an algorithm of their implementation at an operating field.
