Mixture and rheological performance of asphalt binders blended with cecabase warm mix additive

Warm mix asphalt (WMA) is gaining popularity due to its lower production and laying temperatures that benefits the environment. This paper presents the effects of a surfactant based warm additive, Cecabase®, on the rheological properties of asphalt binder and mixture compactibility. The rheological properties of asphalt binder were measured using a rotational viscometer and dynamic shear rheometer (DSR). Asphalt mixture compactibility was evaluated during compaction using the gyratory compactor based on the degree of compaction and compaction energy index (CEI). From the viscosity and DSR test results, the surfactant based warm additive has no effect on the binder rheology. The compactibility test results shows that all of the WMA mixtures exhibit better compactibility than the hot mix asphalt (HMA). The results shows that it requires less effort to compact WMA at 140°C compared with HMA compacted at 170°C. The CEI results show that it will take more energy to compact HMA specimens compared with compacting WMA at different temperatures. Mixtures with lower CEI exhibits better constructability and are desirable, while too low CEI could be an indication of a tender mixture and should be avoided.