Influence of fine particles on frost heaving of crushed rock material in a closed drainage system

This paper presents the results of an experimental study of the frost heave test in closed drainage system and estimation of thermal conductivity and frost penetration depth for used crushed rock material used in the road construction. The influence of fines on the frost susceptibility of crushed aggregates was established by laboratory frost heave test. A total 10 samples with fine content of 5%, 10% and 15% were investigated. This paper presents the results of a laboratory investigation of the influence of fines on the freezing characteristics of well-graded crushed aggregate in a closed drainage system. At the same time some estimation of thermal conductivity and frost penetration depth for all tested samples were made. It was established that even for a closed system, without access of water, frost heave can occur just from redistributing water if fines content exceeding 10% and water content is around 7%. It is also shown that predicted thermal conductivity values, obtained with the Johansen’s model for dry crushed rock, can have an increase on 75% by increasing the dry density on 15%. Finally, rough estimations of the frost penetration depth for crushed rock material were introduced.