Evaluation of interaction between emulsified asphalt and mineral powder using rheology

Abstract

Polymer emulsion can significantly improve the performance of emulsified asphalt but can also increase the complexity of the system, especially after mixing with mineral powder. The objective of this study was to evaluate the emulsified asphalt and mineral powder interaction ability based on rheological properties. First, two types of emulsified asphalt and three types of mineral powders were selected to prepare emulsified asphalt residues and mastics, and their dynamic shear rheological (DSR) properties were measured. Second, the K-B-G* and ΔG* models were used to evaluate the influence of temperature and loading frequency on emulsified asphalt and mineral powder interaction ability. Third, the physicochemical interaction between the emulsified asphalt and mineral powder was measured by a Fourier transform infrared (FTIR) spectrometer. Finally, the significance analysis of temperature and loading frequency was conducted by grey relational analysis (GRA). The mold designed in this study was demonstrated effective in obtaining emulsified asphalt residue samples that were suitable for DSR tests at low temperature. K-B-G* and ΔG* indices are consistent in evaluating the interaction ability between emulsified asphalt and mineral powder. The two indices can reflect the influences of temperature and frequency on emulsified asphalt and mineral powder interaction ability, and they also can reflect the difference in the interaction ability of different mineral powders and emulsified asphalt. No new absorption peak in the FTIR spectrum indicated that the physical interaction between emulsified asphalt and mineral powder is primarily the physical action. GRA can be applied to the significance analysis of temperature and loading frequency, and the temperature demonstrates greater influence than the loading frequency. The cationic emulsifier plays the role of anti-stripping agent and enhances the interaction between cationic emulsified asphalt and acid aggregate. The rheological results can guide the selection of the appropriate emulsifier according to the aggregate using in the project.