Abstract
There is a long history of research on the frost heave mechanism. However, the mechanism of frost heaving is not yet elucidated. Because of this, general understanding which is based on recent research results is not widely permeated, and then erroneous measures are seen in frost heave engineering.
Recognizing this problemes, first, a frost heave process which is deduced from past research results is outlined. Phenomenological features of frost heave and a microscopic structure model of ice lens vicinity are discussed with the research results of properties of unfrozen water, and then a process of ice lens growth is shown.
Second, a macroscopic mechanism of ice lens initiation, which gives the initial condition of the segregating ice lens in heaving, is then proposed. A mechanism of ice lens initiation by breaking the structure in which the pressure of pore ice overcomes the overburden pressure and the tensile strength of the structure is shown, and also another process, which simultaneously functions and depresses the local unfrozen water pressure which is a necessary condition of ice lens segregation is discussed with experimental data.
