Temperature Deformations of Soil Influencing Transportation Continuity in the Arctic Region

Phase transformations of ice in seasonally frozen soils are an inalienable part of the Earth’s cryosphere and affect the balance of the external heat of our planet. These processes depend on natural and technogenic changes in the environment. That is why for the design of engineering structures (roads and railways, quay walls, etc.) built in the Arctic world regions, it is necessary to have a complete understanding of the formation mechanism of the stress–strain state of such soils in a wide range of thermal loads. The study of the nonstationarity of ice, as an important component of the considered medium, is an actual problem. New method for measuring the temperature deformations of frozen soils using fiber-optic Bragg grating sensors can serve as a solution. In the course of the experiments, cylindrical samples of previously frozen soils saturated with water of different salinity were tested. Measurements of the thermal deformations of frozen soil samples were performed in the cold laboratory in the temperature range between 0 and −12 ℃. Fiber Bragg gratings strain and temperature sensors were used to measure the deformation and temperature inside the samples. A number of tests with the samples prepared from Kaolin and Cambrian clay saturated with freshwater, and prepared from fine and silt sand saturated with fresh or saline water, were performed. Thermal deformations of the samples are analyzed depending on the cyclic changes of their temperature.