Impact of warm mix additives on rheological properties of polymer modified asphalt binders

摘要

There are many opportunities to apply warm mix asphalt (WMA) technologies to polymer modified asphalt (PMA) binders by incorporating warm mix additives to lower temperature of the mix during operation (i.e., mixing and compacting). This has become more important since the relatively high temperature is required for processing the PMA binders, resulting in several potential problems such as increasing the fuel energy use, emissions, and odors. This paper describes the rheological investigation of five PMA binders, graded as PG 76-22, containing two warm mix additives (Asphamin and Sasobit) available commercially. The main rheological factors selected in this study were relationships between loading and response as a function of time, temperature, and frequency using a Bohlin dynamic shear rheometer II. Overall, the results suggested that the two warm mix additives positively influenced the performance of the PMA binders. In particular, the use of Sasobit showed the enhanced rutting resistance properties at high pavement temperature and more elastic at lower temperatures and frequencies through all binder sources, while Aspha-min was observed to have an improvement in rutting resistance depending on the sources of binder.