The newly laboratory equipment for exploring of freezing and thawing soils

Abstract

Abstract 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.