The bearing capacity of a pile foundation designed in the conditions of the spread of permafrost soils directly depends on the temperature of the foundation soils that make up the engineering-geological section. When the temperature regime of the soils of the bases, determined at the stage of engineering surveys, is not ensured during the operation of a building measures are developed for temperature stabilization of the soils. As a rule the installation of seasonally operating cooling devices is envisaged. The main criterion for the normal operation of seasonally operating cooling devices is the provision of free airflow of the condenser part with atmospheric air. One of the factors that negatively affect the ventilation mode is partial or full snow cover of the capacitor part. Because of remoteness and length of individual oil and gas production facilities, degree of snow cover cannot be controlled and serviced with the required frequency. Manufacturers in the operating rules of their devices prescribe the need to provide airflow and free access to the condenser of seasonally operating cooling devices. Specialists in do not take into account the decrease in the efficiency of seasonally operating cooling devices when compiling calculation models. As a result technical solutions for pile foundations in a certain period of operation may not perceive the design load.
Considering the harsh operating conditions of oil and gas production facilities in the area of permafrost soils and after analyzing a large array of field observations of snow cover, the authors came to the conclusion that in most cases the requirement of the inadmissibility of snow cover of the capacitor part of the products is not observed for objective reasons. Based on the problems identified above, the authors of the article proposed a technique that allows improving the quality and accuracy of predictive heat engineering calculations. The technique is based on the selection of the heat transfer coefficient of seasonally operating cooling devices, taking into account the uneven snow cover of the condenser part. According to the results of the study, it is proposed to take into account the decrease in the efficiency of seasonally operating cooling devices due to partial or complete snow cover and to control the snow cover of the condenser part of seasonally operating cooling devices with a frequency that allows you to correctly take into account the thickness of the snow cover in the simulation process.
References
1. Gabidullin R.N., Mustafin T.R., The effect of mechanical damage to the condenser fins of soil thermal stabilizers on the efficiency of their work (In Russ.), Territoriya Neftegaz, 2019, no. 12, pp. 64-74.
2. Strizhkov S.N., On the issue of the quality of operation of seasonally operating cooling devices (In Russ.), Zhurnal Geoinfo, 2017, URL: https://geoinfo.ru/product/strizhkov-sergej-nikolaevich/k-voprosu-o-kachestve-raboty-sezonno-dejstvu....
3. Rukovodstvo pol’zovatelya FROST 3D (FROST 3D user manual), URL: https://frost3d.ru/vypolnenie-prognoznyh-raschetov-temperaturnogo-rezhima-merzlyh-gruntov/
4. Rukovodstvo pol’zovatelya “Borey 3D” (Borey 3D user manual), URL: https://www.boreas3d.ru/boreas3d%20user%20manual.pdf
5. Pazderin D.S., Dinamika teplovogo sostoyaniya mnogoletnemerzlykh gruntov v osnovanii zaglublennogo truboprovoda s primeneniem okhlazhdayushchikh ustroystv (termostabilizatorov) (Dynamics of the thermal state of permafrost soils at the base of a buried pipeline using cooling devices (thermal stabilizers)): thesis of candidate of technical science, Tyumen, 2017.
