Experimental and theoretical characterization of frost heave and ice lenses

A series of freezing experiments were conducted to simulate the frost heave in saturated silt samples with variable thermal boundaries. It is shown that before the frost heave occurs, a small amount of pore water is discharged out of the soil due to the sudden freezing of the super-cooled pore water, and that once the frost heave occurs, the total amount of frost heave is approximately equal to the amount of frost heave due to water intake. A formulation is developed which can be used to determine the initiation time of frost heave. The location of the freezing front and the amount of frost heave are calculated, and the calculated results agree well with the experimental measurements. A criterion for ice lens initiation/growth is presented, according to which an ice lens initiates or grows if the volumetric water content is equal to or greater than 1. It is demonstrated that the predicted ice lenses are similar to the observed ones, showing the validity of the criterion.