Heat and water transfers for the frost heave behavior of freezing graded soil

Abstract

Heat and water transfers for the frost heave behavior of freezing graded soil as affected by fine content, cooling temperature, and water supply were investigated in this study. Results showed that, the total frost heave mainly came from the external water supply, and higher fine content and lower cooling temperature led to higher frost heave and more water intake (e.g., 14.62 mm and 186.48 ml for sample under −7.5 °C with 50% fine content). The sample experienced shorter temperature cooling stage with higher fine content (e.g., 8.7 h for sample with 50% fine content), and longer temperature cooling stage under lower cooling temperature (e.g., 13.2 h for sample under −7.5 °C). Higher fine content and lower cooling temperature resulted in higher maximum volumetric water content above the frozen fringe (e.g., 52.33% and 55.63% for samples under −5 °C and − 7.5 °C with 50% fine content, respectively). The thickness of visible ice lenses was proportional to the frost heave and “invisible” ice lenses contributed more to the frost heave. Theoretical predictions of frost heave based on the modified formula showed good agreement with the experiment results with relative error of 2.7%.