Publikace (přehled)

Many pollutants are released and much energy is consumed during the constructions of asphalt road infrastructure. The technologies of warm mix asphalt (WMA) are discussed very often in the scope of sustainable development. The technologies enable the preparation and processing of asphalt mixtures at lower temperatures. This is the way how to decrease the energy consumption and emissions of pollutants as well as to improve the working conditions during the road construction. The processing temperatures can be decreased by the addition of suitable additives into bitumen. We studied the effect of various synthetic waxes on bitumen properties. The emphasis was put on changes in viscosity at high temperatures. The binders contained 3% of synthetic waxes and 97 % of base bitumen. The effect of the waxes addition was studied on changes in (i) basic properties, (ii), equiviscous temperature for 200 mPa.s and (iii) resistance to ageing. The two selected binders were analyzed thoroughly including their rheological properties and storage stability. Polyethylene wax and amine wax were identified as the best additives. The decrease of equiviscous temperature was 8°C for the bitumen with the amine wax and 10 °C for the bitumen with the polyethylene wax. The binders had outstanding storage stability. Furthermore, the additives improved the bitumen resistance to ageing. The possibility of asphalt mixture production at 120 °C was confirmed. Decrease in the mixing temperature was 30 °C compared with the conventional bitumen.