Predicting the Behavior of Asphalt Concrete Pavements in Seasonal Frost Areas Using Nondestructive Techniques

Authors: Vincent C. Janoo; Richard L. Berg; COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH

Abstract:

This report addresses the problem of pavements in seasonal frost areas that are subject to freezing in the winter and thawing in the spring. In the winter, the pavement structure modulus increases because of ice segregation in the unbound base or subgrade, and because of the influence of temperature on the viscosity of the asphalt or concrete. During spring thaw, the pavement foundation can become saturated with water from the thawing ice lenses, thus reducing the structural adequacy of the base or subgrade. With a weakened structure, the pavement can not support the load it was designed for; therefore, one can expect most of the damage to a pavement to occur during the spring thaw. Damage to the pavement structure will reveal itself on the surface in the form of fatigue cracking and rutting, owing to deformation in the base or subgrade. The length of time that a pavement structure is subjected to thaw weakening will vary depending on the frost depth, soil type, degree of saturation and drainage conditions. Pavement strength can be determined using nondestructive testing, such as a Falling Weight Deflectometer (FWD), or existing reduction factors. Determining pavement strength during thaw periods will then allow load the imposition or removal of load restrictions so as to minimize the damage of the pavements.

Limitations:

APPROVED FOR PUBLIC RELEASE