Grant: Discovery Launch Supplement

The overarching goal of this Discovery Grant (DG) proposal is to empower Canada to harness the economic and ecological benefits of high-performance asphalt concrete (HPAC) for the construction of long-lasting, climate-resilient, and cost-effective road infrastructures in cold climate conditions. More than 40% of the national road network falls below the "good condition" standard, meaning that it requires prompt significant maintenance works. Poor pavement conditions not only increase operation costs for all Canadian drivers but also reduce freight transport productivity, contributing to road transport's greenhouse gas emissions, which make up one-third of Canada's total. Considering Canada's current and expected climate conditions (temperate or cold climate most of the year with frequent winter freeze-thaw cycles), cracking of asphalt concrete (AC) has been identified as a major cause of pavement deterioration in Canada. Innovation in AC mix design has led to the development of high-modulus and fatigue cracking resistant pavement materials, known as high-performance AC (HPAC). This has recently attracted interest from the Canadian academia and industry as a compelling solution to the country's pavements cracking issue. However, the performance requirements that define HPAC correspond to foreign contexts, not considering cold weather-related aspects nor specificities of the Canadian road industry, such as resistance to thermal cracking and freeze-thaw cycles. Furthermore, calibration factors used in the mechanistic-empirical pavement design (ME-PD) approach to relate laboratory fatigue performance to real road service life must be defined for Canadian conditions. These factors should consider the country's diverse climates and materials, yet currently, there is no established method for this purpose. Even though certain Canadian industry actors have the expertise to formulate HPAC, the lack of a locally calibrated ME-PD method impedes them from translating their advanced know-how into practical and economical benefits (i.e., optimized road structures). This knowledge gap is creating a mismatch between the industry's capabilities and their practical implementation in the field. The research program proposed for this DG focuses on the redefinition of fatigue performance indicators and field calibration factors for HPAC in the Canadian context. Innovatively, this DG will employ an approach based on intrinsic fatigue damage for the analysis of fatigue life in both laboratory and field settings, overcoming the challenges posed by the high variability of conventional practices. By advancing the state of knowledge regarding the practical application of HPAC in Canada, this DG will contribute to bridging the knowledge gaps that obstruct the implementation of a ME-PD approach in the country. This DG will support highly qualified personnel (HQP), at both graduate and undergraduate levels, in the field of pavement engineering.