Relationship between Uniaxial Thermal Stress and Strain Test (UTSST) parameters and field cracking data of asphalt mixtures from MnROAD test experiment

ABSTRACT

Establishing relationships between the results of laboratory mechanical tests and field performance of the asphalt concrete layer is a necessary step prior to the test implementation at the mix design stage or during production. The objective of this study is to confirm the relationship between the Uniaxial Thermal Stress and Strain Test (UTSST) results and measured field cracking data for test sections at the Minnesota Road Research Project (MnROAD). The interpretation of UTSST results, conducted on reheated plant specimens, highlights the considerable effect observed for the asphalt binder grade on performance; whereas the long-term aging data set suggests a dominant effect of the amount of recycled materials in the mixture. Several UTSST parameters resulted in robust relationships with the mix Bending Beam Rheometer (BBR) and Semi-Circular Bending (SCB) test parameters, including the UTSST cracking resistance index (CRI_Env) with the mix BBR strain at failure. The UTSST parameters exhibited the most significant correlations with load and non-load field cracking data. Some of the prominent relationships observed corresponding to the shoulder cracking data with the UTSST glassy temperature and $\mathrm{\Delta }{T}_{mix}^{UTSST}$, suggest an improved resistance to non-load related cracking due to a delayed transition of the asphalt mixture to the glassy stage.

KEYWORDS:

• Asphalt mixture performance
• thermal cracking
• asphalt test sections
• pavement thermal stresses

Acknowledgments

The authors greatly acknowledge the Minnesota Road Research Project (MnROAD) for providing materials and collecting field distress data along with thermocouple data required to complete the analysis of the evaluated test sections.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

The authors confirm contribution to the paper as follows: study conception and design: E. Hajj and P. Sebaaly; data collection: N. Morian and M. Vrtis; analysis and interpretation of results: E. Hajj, N. Elias; draft manuscript preparation: N. Elias and E. Hajj. All authors reviewed the results and approved the final version of the manuscript.