Improvements to the Australian wheel tracking protocol for asphalt deformation resistance measurement

With the introduction of new pavement technologies, asphalt performance-based mixture design has become increasingly important in the pavement industry. A key consideration for performance-based mixture design is to ensure that laboratory performance-indicative tests link sample preparation and test parameters to expected in-field conditions appropriately. For the performance assessment of deformation resistance, the most common test method in Australia is the wheel tracking test. Recent research involving the assessment of stone mastic asphalt deformation resistance properties identified several elements of the Australian wheel tracking protocol requiring improvement. This paper details recommendations to improve the Australian wheel tracking protocol in terms of sample preparation and laboratory test parameters, to increase reliability of the results and to better link laboratory assessment to in-field performance.