Investigation into the Adhesion Performance of the Recycled Asphalt Mastic–Limestone Filler Interface Using the Pull-Off Test and Surface Free Energy Theory

This study aims to evaluate the adhesion performance of the recycled asphalt mastic (RAM)-limestone filler interface and the contribution ratio (CR) of mineral filler to the adhesion performance of the RAM-limestone filler interface. Using the pull-off test and surface free energy theory, the impacts of aged asphalt binder dosage, resurfacing dosage, and filler-asphalt binder ratio (F/A) on the grip capacity of the RAM-limestone filler contact were examined. The CR of mineral filler to the adhesion performance of the RAM-limestone filler interface under different influencing factors was calculated. Results show that the bonding strength and adhesion work of the RAM-limestone filler interface reach their best when the aged asphalt binder dosage is 20%. As the rejuvenator dosage increases, the RAM-limestone filler interface's adhesion performance declines. As the amount of mineral filler increases, the bonding strength of the RAM-limestone filler interface first rises and subsequently falls. When the dosage of aged asphalt binder is 20%, the mineral filler's CR to the RAM-limestone filler interface's adhesion performance is at its highest. The impact of mineral filler on the RAM-limestone filler interface's adhesion performance can be lessened by increasing the amount of rejuvenator. The greatest CR of mineral filler to the adhesion performance of the RAM-limestone filler interface occurs when the F/A is 1.4.