[Abstract] Moisture damage is a prominent problem of asphalt pavements, and the bond strength between asphalt and aggregates is a crucial factor that influences the capability of asphalt to resist moisture-induced damage. In this paper, binder bond strength (BBS) test was conducted to evaluate the effects of various modifiers and additives of different amounts on bond strength between asphalt and aggregates. Furthermore, the influence of styrene–butadiene–styrene (SBS) on adhesion behavior of asphalt binder was investigated through gel permeation chromatography (GPC) test. Finally, the results of BBS test were compared with the findings obtained from Hamburg wheel-tracking device (HWTD) test which reflected the moisture sensitivity of mixtures under wet conditions.
Results indicated that gilsonite, high-density polyethylene, and polyphosphoric acid improved bond strength of base asphalt; SBS had no positive effects on asphalt adhesion properties, and SBS at a low amount reduced the bond strength. Ethylene bis-stearamide wax, crumb rubber, terminal blend (TB) powder-rubber, and compound modifier TB powder-rubber+SBS decreased the bond strength. The GPC test results showed that SBS possibly did not actively contribute to the formation of bond strength between asphalt and aggregates. The test data for BBS and HWTD tests under wet condition confirmed that there was no discernible correlation between these two tests when evaluating adhesion properties of different modified asphalt. However, the results of BBS test were in accordance with those of HWTD test when evaluating the adhesion of asphalt with different amounts of the same modifier and reflecting the mixture resistance to water damage.
