Abstract
Base granular materials are generally considered non-frost susceptible, which is an adequate assumption based on widely recognised frost criterions. However, their frost susceptibility is influenced by the presence of water that can unavoidably penetrate pavement structures. Even if unsaturated, freezing of unbound granular materials causes a net volume gain and an increase in water content which affect pavement performance during the spring period. This paper presents the results of a laboratory investigation on the effect of gradation on frost susceptibility, quantified with the segregation potential (SP), of three aggregate sources. The results suggest that SP values for all sources are strongly related to a fine particles state parameter. Moreover, the source influence was found to be described adequately with a parameter describing fine particles grain size distribution uniformity and fines specific surface. A model is proposed which combines gradation and mineralogical source effects on frost susceptibility of base granular materials.
Acknowledgements
The authors wish to thank the MTQ, Fond Québécois de Recherche sur la Nature et les Technologies (FQRNT) and Transport Association of Canada (TAC) for their financial support. The authors wish to acknowledge the technical contribution of laboratory technician Christian Juneau and the contribution of research assistants who took part in the sample preparation, characterisation and testing phase of this study.