Analysis of Seasonal Bearing Capacity Correlated to Pavement Deterioration in Cold Region

Resumé

The Laboratoire Central des Ponts et Chaussées (France) and the Ministère des Transports du Québec (Canada) have developed a joint research project on the behaviour of pavements in a cold region. This project aims to increase understanding about fatigue damage of pavements under the combined effect of traffic and a decrease in bearing capacity during the thawing period. An experimental site was constructed in Quebec in 1998 and its behaviour was monitored for six years. Pavements with a cement-treated base and a hot-mix asphalt base were selected. Two test beds of each type were constructed. One of these two test beds was thermally insulated by a layer of extruded polystyrene, while the second was not, so  that the researchers could distinguish between traffic and climate effects. This paper presents the analysis of the seasonal variation of bearing capacity related to deflection, subgrade modulus and tensile strain. Also, an analysis of the results describes the difference observed between the quasi-static and dynamic responses and the relationships between traffic loading and pavement performance.