Dynamic Rheological Properties and Microscopic Characteristics of Ash Mastics

Abstract:

Ash components were extracted from button rock asphalt，which mixed with the pure asphalt with the mass proportion of ash and asphalt as 0.8∶1. The dynamic shear rheological tests，Xray diffraction analysis techniques and the scanning electron microscopy were applied to the study of the rheological properties of ash and mineral filler mastics, and microscopic characteristics of ash and mineral filler. The results show that ash mastics has a better high temperature rheological properties than filler mastics, with the high temperature grade up to PG76 ℃. However, the two mastics have a similar trend for the changes of performance when the temperature and the frequency increase. There are some protrusions and depressions structure in ash material with a fluffy scalelike surface. The vertical micro scale amplitude reaches 0.35 μm and the specific surface area is much larger than that of the mineral filler. A welldeveloped porosity and ditch grain structure can enhance the adsorption of filler for asphalt, and the bond strength of asphalt and aggregate improves. The film thickness of the structure of asphalt increases, which prevents the water molecules from damaging the asphaltaggregate interface.