STUDY ON THE FROST HEAVE RATIOS IN TRIAXIAL DIRECTIONS OF SOIL BASED ON EFFECTIVE STRESSES CONSIDERATION

Abstract

Frost heave tests under the triaxial stress condition are performed to study the influence of several factors on the frost heave ratios in triaxial directions. The effective stress increase under small confined stress due to the decrease of pore water pressure during freezing makes the frost heave ratios smaller in both the heat flow and its perpendicular directions. The earth pressure increase in the heat flow direction makes the frost heave ratio smaller in the heat flow direction while larger in the perpendicular direction. Because of consolidation in unfrozen soil, the frost heave ratio in the heat flow direction of soft soil is smaller than that of hard soil. The numerical model of the frost heave ratios considering these factors as well as the traditional experimental formula of triaxial frost heave, is proposed. The validity of the model is confirmed by comparing the analytical values with experimental results of the frost heave ratios.