Characterizing the Complex and Zero Shear Viscosity Properties of Polymer-Modified Asphalt Using Master Curves

The performance of the flexible pavement is based on the characterization of hot mix asphalt (HMA). The alterations in climatic conditions and traffic loading influence the rheological properties of asphalt. The asphalt viscosities are an important parameter of asphalt that gives resistance to permanent deformation and stability in the various application areas. Polymer modification can be used to enhance Viscoelastic properties of asphalt binder to enhance its resistance against rutting and cracking. This study developed polymer-modified asphalt samples and tested them using a dynamic shear rheometer at seven temperatures (46, 52, 58, 64, 70, 76, and 82 oC) for frequency sweep (1 to 100 rad/s). Master curves were developed by choosing 64 oC as a reference temperature and applying shift factors. The results depicted that the polymer modification has a substantial influence on enhancing the elastic behavior of asphalt. Attock PMA sample is stiffer compared to laboratory polymer-modified asphalt (PMA) samples, which is determined by the high zero shear viscosity. The behavior of PMA samples at 1.7% and 2.0% of polymer content is similar, which indicates that 1.7% of polymer content can be used as the optimum value for polymer modification. A 2nd-degree polynomial model has the best fit for the master curve of complex viscosity with R2 = 0.921. The values of ZSV indicated that the PMA samples are resistant to permanent deformation, because it increases the stiffness and elasticity of the samples. These findings involve substantial information as to the practical use of polymer-modified asphalt and the way it can be applied in the improvement of pavement performance, durability and offer valuable information on how to select materials to use in designing an asphalt mix.