The effect of glass beads sizes and surface treatment on the bonding performance of asphalt pavement marking

Glass beads (GBs) are commonly used for pavement marking to provide continuous reflective capabilities at night. This evaluation aimed to assess the influence of particle size and surface treatment on the bonding performance between the marking and asphalt pavement surface. GBs were modified using silane coupling agent and hydrofluoric acid for enhancing the bond with the marking paints. The effectiveness of the modification and the changes in functional groups on the surface of GBs were evaluated. Additionally, image processing technology was employed to analyze changes in the roughness of GBs after surface treatment. Subsequently, the influence of GBs with different particle sizes and modification methods on the adhesion properties was investigate through wheel abrasion test. The bonding strength between the marking paint and the asphalt pavement surface was then explored through direct pull-out test, considering different dosages, particle sizes, and modification methods of GBs. The test results indicated that surface-modified GBs exhibit improved bonding properties with paints. Notably, GBs modified by coupling with hydrofluoric acid and silane coupling agents demonstrated the optimum improvement in bonding behavior. The contact area between the wheel and pavement marking was also investigated in terms of various GBs particle sizes. The premixed 35 wt% modified GBs paints with 100 mesh size exhibited the strongest bonding performance with the asphalt pavement surface. This study provides the applicable technique for enhancing the bonding performance between marking and pavement surface for a better abrasion resistance and thus a longer service life.