Monitoring and Modeling the Variations of Structural Behavior of a Flexible Pavement Structure during Freezing

Abstract

This paper presents the results of a study carried out to monitor the structural behavior of a flexible pavement in cold regions, which is significantly affected by environmental factors and traffic loads. In this study, a heavy vehicle simulator was used to simulate traffic load and to provide enough cooling energy to create a freezing environment. The mechanical response of the typical Quebec flexible pavement structure during freezing was investigated using this research tool. An empirical model was also proposed and validated to describe the effect of each pavement layer on the mechanical behavior variation during freezing. The results show that the changes of moisture content and matric suction for unbound materials have a good correlation with the frost state of surrounding materials. The mechanical responses, including strains and stress, experience a regular variation along with the increase of frost penetration. The model indicates that the asphalt layer is playing a significant role in all the mechanical response variations. As for the role of other layers, the mechanical response variation for a given layer is mostly dependent on its condition and its neighboring layers.