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The city of Arkhangelsk has the complicated geological conditions, particularly wide spread occurrence of soft ground such as peat and mud. The average annual atmospheric temperature is about +0.8 о С and that enables the seasonal frost penetration up to 1.8…2.2 m. Usually the frost penetration causes damages to low-rise buildings, road paving, and pipelines. But the authors unexpectedly found in the process of their practical activities deformations of a building supported by 18 meter piles which were caused by the frost heave of a mud. The building is a cooling house designed for fish storage at the temperature of-22…-24 о С which has been operated since 1985. It was found by drilling boreholes that the mud under the center of the building was frozen at the depth from 3.8 to 8.1 m. The floor uplift reached 18 cm, the inner columns uplift-13 cm and the building was taken out of service. The numerical simulation data for 29 years of the building operation period performed by the Geostudio software correlate quite close with the data obtained by drilling the boreholes. The achieved experience may be useful for construction of ice rinks, cooling houses as well as for regular not heated storage buildings. As for the latter buildings located in the regions with the average annual atmospheric temperature about 0 о Сthe frozen ground layers may continue and their thickness may increase for several years.

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Frost heaving is a challenge for geotechnical engineers in cold climate. Frost heave depends on two factors: the freezing rate and the velocity of water migration from unfrozen to frozen soil. The article deals with the existing apparatus for exploring frost heave which are systematized according to their purpose (measured parameters), design features and experimental conditions. The authors proposed the ways for improving laboratory equipment and presented newly developed apparatus for studying both the frost heaving and its consequences. The article presents apparatuses that allow controlling the freezing rate of soils by step-by-step movement of the freezing cell along the sample and providing even movement of the frost front in center and edges of the soil sample. Control of water migration to the frost front is carried out by making a vacuum in a base plate or using a porous item with a given water permeability. To study the impact of cyclic freezing-thawing on water permeability both along and across the cryogenic texture the authors developed a special apparatus in which horizontal permeability test is performed through the perforated double walls of multi-ring cell, vertical test-through bottom and top porous discs.