Moisture damage in asphaltic mixtures is defined by the loss of durability and resistance caused by the effect of moisture. The most common way to improve moisture damage in asphaltic mixtures is to use anti-strip additives. This study tended to use dry resin polymer additive to make a moisture-resistant asphaltic mixture. Two types of aggregate indicating different sensitivities against moisture were studied. In order to compare the effect of this material with other anti-strip additives, this study evaluated the effect of hydrated lime on reducing moisture damage and comparing its effect with dry resin polymer additive. The effect of these materials was evaluated by mechanical and thermodynamic concepts using indirect tensile ratio and surface free energy. The results indicated that dry resin polymer used in this study increased alkaline content and reduced acidic content of bituminous surface free energy, resulting in more adhesion between acidic aggregates which are more sensitive to resistance. It also improved bitumen-aggregate adhesion and reduced strip rate. Moreover, hydrated lime as an aggregate anti-strip agent and dry resin polymer as a bituminous modifier significantly increased the resistance of warm asphalt mixtures against moisture. The results of this study show that dry resin polymer can be used as an anti-strip agent instead of hydrated lime with operational problems.

Rutting is a common damage of flexible pavements, reducing the service life of asphalt pavement. Due to laboratory limitations, asphalt mixtures are subjected to different curing times (since construction until placement in the test chamber) and thermal equilibrium times (since placement in the test chamber until the beginning of the test) before rutting tests. Neglecting these factors can lead to errors in the laboratory results. Therefore, the present study attempted to investigate the effect of curing times of 1, 2, and 3 days at 25ºC and thermal equilibrium times of 2, 4, and 6 hours on the rutting potential of different hot-mix asphalt (HMA) mixtures. Results of rutting tests showed that the rutting potential of asphalt mixtures decreases by increasing the curing time, while the permanent deformation at the end of loading cycles and rutting potential increase by increasing the thermal equilibrium time. Additionally, the results of statistical analyses revealed that curing time and thermal equilibrium time change the rutting potential of asphalt mixtures.