Year-round thermal stabilization of permafrost soils during road construction in the northern climatic zone of Russia

¹ Emperor Alexander I St. Petersburg State Transport University, 9, Moskovsky ave., 190031 St. Petersburg, Russia
² Scientific and Innovation Center “Dispersed Systems” (NVC “DISIST”), St. Petersburg, Russia

^* Corresponding author: pgups60@mail.ru

Abstract

The device for year-round cooling of permafrost soils is designed to ensure the construction and operation of roads and railroads in the tundra zone. It includes pipes buried in the ground near the roadbed, a wind turbine powering an electric current generator, an absorption-type cooling unit, and an exhaust fan ensuring the flow of atmospheric air through the pipes. During the long and cold winter, the pipes laid in the ground provide deep freezing of the ground beneath a thick layer of snow. In spring and autumn, at temperatures close to 0°C, the air in the pipes is forcibly cooled by the cooling unit. In summer, at air temperatures exceeding 10°С, air movement through the pipes is blocked. In conditions of short summer, low levels of the sun above the horizon, the high albedo of snow and ice, and their low thermal conductivity, snow deposits remain on the ground throughout the summer period, and in the subsequent winters, accompanied by snowfalls, they intensify. Around a roadway built on permafrost, a protective snow layer is formed, preventing the flow of heat from the atmosphere and solar radiation into the ground. The protective layer can exist for decades, even if the Earth’s climate changes globally. The article presents hydraulic and thermal calculations, explaining the operation of the device in question.