Effect of frost heave on a silt column filled with rubber-asphalt-fiber

Frost damage to railway subgrade restricts the normal operation of railways and roadways in seasonally frozen areas. This paper proposes using stress release holes as a measure to alleviate frost heave force. Using a prediction model based on heat conduction and the seepage of unsaturated soil, a one-dimensional freezing experiment is conducted to calculate the frost heave of a soil column. Results suggest that stress release holes filled with mixed-materials can effectively alleviate frost heave and reduce vertical frost heave deformation from 36.8% to 65.3%. It is recommended that stress release holes be filled with a low stiffness, non-shrinking, cylindrical mixed-material which improves their waterproofing and strength enhancement. Furthermore, the burial depth of the stress release hole filling be kept above the height of supplementary water level, and that the filling's elastic modulus hold a value of 1/4 to 1/2 that of the surrounding soil.