Frost heave characteristics and scale effect of stationary frost heave

The purposes of this study are (1) derivation of an empirical formula which can compute the stationary heave (the last ice lens growth) amount, (2) determination of a scale effect which regulates heaving properties in the stationary frost heave phase. Open-type frost heave tests have been conducted under fixed boundary-temperature condition for undisturbed alluvial clay with three variables (1) overburden pressure, (2) specimen length, and (3) temperature gradients. Each test has the time duration of 100 to 1000 hours. A relation between heave rate and elapsed time has been found for the stationary heave phase. Integrating this relationship with respect to time, an empirical formula is proposed to determine heave amount during the stationary heave phase. Using this formula together with the concept “Segregation Potential” (Konrad,1981), it is possible to (l)compute heave amount in the stationary heave phase for varying pressure, specimen length, and temperature gradient, (2)propose the scale effect of the frost heave test by substituting the non-dimensional indexes for heave amount and time.