The design of cost-effective, long-lasting pavements is of high importance in Canada, where daily and seasonal temperature varies significantly. Moreover, the abrupt changes in the global climate and its inverse impacts on transport infrastructures over the last decade require planning for necessary adaptations to mitigate those effects. More research should be conducted to address the potential impacts of climate change on the pavement design. A mechanistic analysis that considers thermomechanical loads could be a tool to study the possibility of variations in frequency or severity of pavement failure due to climate change. Such a model when is fed with site-specific material properties, traffic load, temperature profile, and pavement parameters, would more accurately predict the performance, serviceability and safety requirements. The pavement design may involve identifying tens of parameters, which makes it complex for pavement engineers.
The current study presents a finite element analysis of flexible pavements to evaluate thermal- and traffic-induced stresses for a selected highway cross-section in Canada. The original surface layer is asphalt concrete for which a linear viscoelastic behavior is assumed. Other layers of the flexible pavement were assumed elastic. The annual temperature profile of the studied construction site was obtained from the Long-Term Pavement Performance (LTPP) database. The change in layers stiffness due to air temperature was simulated by considering temperature-dependent material properties. The outcome of the finite element simulation was implemented into the Ontario pavement design guide to evaluate the design life of the studied cross-section. The outcome of this study was also compared with the AASHTO (1993) design procedure to investigate the similarities and discrepancies between the two methods.
The ultimate goal of this project is to develop an online, user-friendly interface to ease the implementation of the pavement design guide in Canada.