Low-Temperature Performance of Toner-Modified Asphalt Binder

Waste nanotoner is a semiheavy waste material that can be very dangerous to the environment. It can be added to original asphalt binder to enhance some rheological and mechanical properties of the asphalt binder. The objective of this study is evaluation of the effect of waste nanotoner modification on low-temperature properties of neat asphalt binder. Low-temperature characterizations of toner-modified asphalt (TMA) and original asphalt binder were studied by using both experimental and viscoelastic modeling approaches. A bending beam rheometer (BBR) was used to measure creep compliance of neat and modified specimens as a constitutive viscoelastic function. Flexural creep stiffness and rate of stress relaxation were calculated, implementing the BBR results. In addition, for better investigation of low-temperature behavior of modified asphalt binders, two indices were used, including dissipated energy ratio (DER) and derivation of creep compliance (DCC) based on viscoelastic modeling and implementing the Burgers model. Also, differential scanning calorimetry (DSC) testing was performed for determining the glass transition temperature of asphalt binder in the presence of waste nanotoner. This study shows that waste toner can be used as a useful modifier to improve low-service-temperature characteristics of asphalt binders up to 8% of neat asphalt binder's weight. In addition, this research shows that implementing derivation of creep compliance can reflect the effect of waste nanotoner modification on the microstructure of an asphalt binder at low temperatures.