Abstract
The recycling of crumbled waste tire rubber (CWTB) is a major environmental problem facing mankind, and the incorporation of CWTB as a modifier into asphalt is an extremely promising approach. However, the modification mechanism of CWTB to asphalt is not well understood, which restricts the development of CWTB-modified asphalt. In this study, the mechanism of CWTB modification of asphalt was explored in depth by dynamic mechanical analysis (DMA), fluorescence microscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and molecular dynamics (MD) simulations. The results of the study showed that CWTB enhanced the high temperature performance of the base asphalt. The microscopic mechanism by which this phenomenon occurs is that CWTB has the largest binding energy with the aromatics (1100–1400 kcal/mol), followed by the saturates (700–900 kcal/mol), followed by the resins (200–450 kcal/mol), and the smallest binding energy with the asphaltenes (110–160 kcal/mol), which causes CWTB to absorb the light components of the asphalt (aromatics and saturates). In the process of absorbing the light components, CWTB will gradually swell, which causes CWTB to bind more and more tightly with the base asphalt, and eventually the good high temperature performance of CWTB is transferred to the base asphalt. The macroscopic manifestation of this process is that the rutting factor of CWTB modified asphalt is significantly higher than that of virgin asphalt. This study can provide basic theoretical support for the application of CWTB modified asphalt.
Estimation of rutting characteristics of waste tire rubber-modified asphalt binder using GPC
