Investigation of the Effect of Filler on Cohesive Bond Strength of Asphalt Mastic Using Binder Bond Strength (BBS) Test

Water damage leads to spalling and loosening of asphalt pavement, which is ultimately due to a reduction in the bond strength of the asphalt mastic. The filler, as an important component of the asphalt mastic, has a great impact on the various properties of the asphalt mastic and even the asphalt mix itself. Therefore, it is important to study the influence of fillers on the performance of asphalt mastic. In this paper, the various properties of twelve types of fillers, including mineral powder, mineral powder partially replaced with cement, slaked lime, and recycled powder, and their effects on the bond strength of asphalt mastic are investigated. Binder bond strength (BBS) was used to evaluate the performance of the different asphalt mastics. The moisture resistance of the asphalt mastic was evaluated by measuring the bond strength of the asphalt mastic after treatment in a water bath. A grey correlation analysis was then carried out to derive the relationship between the filler index and the bond strength of the asphalt mastic. The results show that the addition of slaked lime and cement helped to improve the moisture resistance of the asphalt mastic. The fineness modulus and other indicators have a great influence on the bond strength of asphalt mastic. The interaction between hydrothermal coupling and filler type has a non-negligible effect on the moisture resistance of the asphalt mastic.