Development of Activated Waste Tire Rubber Composite-Modified Asphalt and Its Performance

ABSTRACT To enhance the low-temperature fatigue performance and structural stability of rubber-modified asphalt (RA), activated waste tire rubber powder (ARP) was developed through microwave desulfurization, and activated waste tire rubber composite-modified asphalt (ARA) was prepared. The conventional properties, rheological performance, and microstructure of ARA were comprehensively tested. The results indicate that ARA significantly improves the high temperature, low temperature, and stability compared with RA. The high-temperature resistance to permanent deformation and the elastic recovery ability of ARA were found to be significantly improved. The comprehensive performances of ARA show improvement compared to styrene-butadiene-styrene-modified asphalt as the resin content increases and the ARP decreases. Nuclear magnetic resonance and Fourier transformation infrared spectroscopy analysis indicate that the reduction in internal cross-linking structures and the breaking of chemical bonds in ARP enhance its compatibility with the base asphalt. Furthermore, the formation of a three-dimensional network structure through reactive blending is fundamental to the overall performance improvement of ARA. The performance benefits of ARA in asphalt mixtures are comprehensively confirmed, providing theoretical guidance for the efficient use of waste tire rubber powder in road engineering.