ABSTRACT
The main advantage of using synthetic waxes for bituminous binders and asphalt mixes is reducing of the viscosity and better workability at lower paving temperature. It makes possible to reduce compaction temperature of asphalt mixtures which are related to energy saving in the production and laying of asphalt mixtures in comparison with conventional HMA. Another advantage is the possibility to increase technological time interval for the transport and processing. There are many additives to reduce working temperatures for asphalt mixtures and this area noted considerable progress in the past 10–15 years. Currently there are developed and tested a new generation of waxes, with using various bases—traditional FT waxes, fatty acid amides, as well as polyethylene waxes and waxes derived from extracts of sugar cane. The article deals with comparison of the selected types of synthetic waxes mixed with pure bituminous binder gradation 50/70. The properties of bituminous binders were evaluated using the basic empirical tests, rotational viscosity, MSCR test and oscillatory test using the Dynamic Shear Rheometer (DSR). Subsequently, the individual binders were used for the production of asphalt mixture ACsurf 11 at reduced temperature. The asphalt mixtures were tested for porosity, water sensitivity (ITSR), stiffness modules, resistance to permanent deformation and low temperature characteristics. The results show that the use of synthetic waxes may reduce the operating temperature of production and compaction of asphalt mixtures. However great attention should be given to the potential negative effects that can be caused by both chemical composition of the wax and more often to so improved workability at reduced temperature, that there is a significant decrease in porosity. Attention is also focused on the connection between performance based characteristics of asphalt mixtures and bituminous binders.
