Waste tire rubber powder enhances Asphalt’s low-temperature performance and viscoelastic temperature interval as revealed by dynamic mechanical thermal analysis

Asphalt, a typical viscoelastic material, significantly affects the performance of asphalt mixtures. Dynamic mechanical thermal analysis (DMTA) is employed to examine the viscoelastic properties of asphalt and investigate the effects of heating rate and loading frequency on its phase-transition characteristics. The dynamic mechanical response curves and characteristic temperatures of asphalt are determined, providing a basis for evaluating its properties. The results show that the temperature spectrum of mechanical response parameters and the phase-transition temperature (PTT) shift to higher temperatures with increasing heating rates and loading frequencies. Heating rate and the logarithmic value of loading frequency exhibit a linear relationship with the phase-transition temperature. A three-dimensional spatial relationship model is established to predict the PTT under various test conditions. T 1 , T 0 , and T g are used as dynamic indicators of low-temperature performance, and their ranking is consistent with BBR results. Adding SBS or waste tire rubber powder modifiers improves the low-temperature performance of neat asphalt, with rubber asphalt demonstrating superior performance compared to SBS-modified asphalt. This highlights the potential of using waste tire rubber as a value-added modifier in eco-friendly asphalt materials. For high-temperature performance evaluation, neat asphalt and modified asphalt require separate analysis based on T 2 . The viscoelastic temperature interval (VTI) provides a phase-transition-based candidate service temperature interval for asphalt. Incorporating SBS modifiers or rubber powder into neat asphalt effectively broadened the viscoelastic temperature interval, with rubber asphalt exhibiting the widest VTI.