Effect of Asphalt-Aggregate Adhesion on Mechanical Performance of Stone Matrix Asphalt under Freeze-Thaw Cycles

Asphalt pavements often experience damage from freeze-thaw cycles in seasonal frozen regions, and asphalt-aggregate adhesion is essential to asphalt mixtures' ability to withstand freeze-thaw damage. To quantitatively investigate the effect of asphalt-aggregate adhesion on mechanical performance of asphalt mixtures under freeze-thaw cycles, in this study, loose asphalt stones were prepared with coarse aggregates, and the quantitative boiling test was performed to evaluate the asphalt-aggregate adhesion property under freeze-thaw cycles at first; subsequently, the high-temperature creep and low-temperature splitting test were adopted with the stone matrix asphalt (SMA) to evaluate the mechanical performance under freeze-thaw cycles; finally, the gray relation analysis (GRA) method was used to analyze the relationship between the asphalt-aggregate adhesion property and mechanical performance. The results suggested that the asphalt-aggregate adhesion property decreased rapidly as the freeze-thaw cycle increased. The high-temperature viscous strain increased 346.13%, and the low-temperature strain energy decreased 14.34% after 21 freeze-thaw cycles. Through the GRA method, it was found that asphalt-aggregate adhesion properties with 4.75 and 9.5 mm sieve-size aggregates had a greater impact on the elastic and viscous properties of SMA, respectively. This study contributes to the design of SMA in seasonal frozen regions and provides a reference to study the damage mechanism of other types of asphalt mixtures in seasonal frozen regions.