Rheological characterization of asphalt emulsions residues

This paper presents the result of an effort to characterize asphalt emulsions that are typically used in cold in-place recycling applications using the current specifications for asphalt binders. Four asphalt emulsions were investigated: CRS-2P, CSS-1, EE, and HFMS-2P. The emulsions were cured using two methods: (1) cure in air at room temperature (air-cured); and (2) use a modified rolling thin film oven test (RTFOT) approach (RTFOT-cured). The air-cured samples were also aged in the pressure aging vessel. The residues were tested using the bending beam rheometer (BBR) and the direct tension test at low temperatures and the dynamic shear rheometer at high and intermediate temperatures. The methods described in AASHTO M320 and MP1a specifications were used to determine the critical temperatures for the four asphalt emulsions and master curves of the absolute value of the complex modulus G* were obtained to investigate the rheological behavior of the residues.