Prediction of Winter Roughness Based on Analysis of Subgrade Soil Variability

Frost action is a major cause of pavement deterioration in cold climates. Thermal cracking, differential heaving, and loss of bearing capacity during spring thaw have often been mentioned as the main mechanisms involved. Frost heave observed on pavements built over frost-susceptible subgrades can reach 200 mm in the Canadian climatic context. The problem is mainly because frost heave is rarely uniform. As a result, pavements tend to become rough during winter. Research recently conducted at Laval University in Quebec City, Quebec, Canada, has shown that winter roughness is related to the variability of subgrade-soil properties. A relationship between the variability of soil frost susceptibility and the ratio of winter and summer roughness has been developed. A new approach, based on the relationship, is proposed to help pavement designers to predict and mitigate winter roughness problems.