Moisture resistance of asphalt mixtures containing epoxy resin additives and limestone and siliceous aggregates

This research evaluated the effect of epoxy resins on the moisture resistance of asphalt mixtures of each bitumen and aggregate (limestone and siliceous) combination by measuring their surface free energy characteristics. The laboratory method measured the contact angle of several probe liquids called the Sessile Drop method. Bitumen polarity, cohesion energy, adhesion energy, bonding energy, energy parameter related to adhesion performance and energy parameter related to wetting performance of aggregate surface by bitumen for each combination of bitumen and limestone and siliceous aggregates were investigated. The results show that epoxy resins increase the polarity of bitumen, but they do not have a positive effect on increasing the cohesion energy of bitumen. For all the studied bitumen-aggregate compounds containing epoxy resin, the adhesion and wetting performance has increased compared to the compounds containing base bitumen, which indicates the proper performance of this additive in improving the moisture resistance of asphalt mixtures.