The role of wax in asphalt

Asphalt concrete, as a good road construction material, has been used at different scales on roads at all levels in China, especially in the field of high-speed access roads are widely used. Most of the existing asphalt mixes use high temperature mixing and paving, rolling construction.

Usually, the mixing temperature of hot mix asphalt is 160~180℃, during the high temperature mixing and paving process, the asphalt material will release a lot of harmful substances such as COx, SO2, NOx and particulate pollutants, which has an extremely negative impact on the health of construction personnel and the natural environment. In order to solve the pollution problems during the mixing and construction of hot mix asphalt mixtures, many studies have been carried out by domestic and foreign road researchers. The aging properties of warm mix asphalt have been studied with the help of microscopic means. It can be found that PE wax is a good modifier for improving the contamination of hot mix asphalt mixtures.

To this end, this paper preferably selected different types of PE wax and asphalt materials, the preparation of a variety of modified asphalt materials with warm mix effect, through the three major indicators of the test system to study the type of PE wax and the influence of the amount of asphalt high and low temperature performance, through the viscosity test to evaluate the rheological properties of different types of PE wax modified asphalt, on this basis, the use of SEM and FTIR analysis means to explore the PE wax warm mix modification mechanism, which can provide a reference for the application of warm mix modified asphalt in the construction of energy saving and emission reduction.

(1) PE wax: high-density oxidized PE wax and 3001 PE wax as warm mix asphalt modifier, the preferred two PE wax technical performance indicators are shown in Table 1. PE wax application of 0.10%, 0.15%, 0.20%, 0.25% and 0.30% of the asphalt mixture mass.

(2) Base asphalt: Shell 90 # matrix asphalt and SBS modified asphalt, its technical performance indicators are shown in Table 2.

(3) Brinell viscometer: DV1MHB high viscosity Brinell viscometer, made in Germany; scanning electron microscope: JSM type, made in Japan, the magnification of 1000 ~ 10000 times; Fourier transform infrared spectrometer: TENSOR27 type, made in the United States.