The Research for Surface Properties of Steel Slag Powder and High-Temperature Rheological Properties of Asphalt Mortar

In order to evaluate the feasibility of steel slag powder as filler, the coating properties of steel slag and limestone aggregate were compared by water boiling test, the micro morphology difierences between steel slag powder and mineral powder(limestone powder) were compared by scanning electron microscope(SEM), and the high-temperature rheological properties of asphalt mortar with difierent ratio of filler quality to asphalt quality(F/A) and difierent substitution rates of mineral powder(S/F) were studied by dynamic shear rheological test. The results show that the surface microstructure of steel slag powder is more abundant than that of mineral powder, and the adhesion of steel slag to asphalt is better than that of limestone. At the same temperature, the lower the ratio of S/F is, the greater the rutting factor and complex modulus will be. In addition,the complex modulus and rutting factor of the asphalt mortar increase with the increase of F/A, and the filler type and F/A have a negligible efiect on the phase angle.