Laboratory investigation into the effects of working temperatures on wax-based warm mix asphalt

• The wax improves constructability parameters at low temperature of compaction.
• The thermal dependence of asphalt concrete reduces with wax.
• Fatigue resistance of WMA is independent from the temperature of compaction.
• WMA is more susceptible to damage from repeated loads than HMA.

The comparative laboratory investigation described in this paper focuses on the effects of artificial wax as an additive for warm mix asphalts (WMAs). The investigation was performed in the Road Research Laboratory at the Politecnico di Milano, and it has been divided into two main phases to evaluate the working temperatures on: (i) compaction and volumetric parameters and (ii) the mechanical performance of two different asphalt mixtures for wearing courses. Results showed that mixtures containing wax are stiffer at low temperatures and produce greater deformations than traditional mixtures, whereas wax does not significantly influence fatigue resistance at 20 °C.