Performance and VOCs emission inhibition of high-content waste rubber powder modified asphalt and its mixture

The high-content waste rubber powder (WRP)-modified asphalt (WRMA) has poor storage stability and tends to produce many volatile organic compounds (VOCs). This study aimed to research the influence of incorporating high-content WRP on the performance enhancement and VOCs emission of asphalt and its mixtures. The storage stability, rheological properties and cracking resistance of WRMA were tested. Further, the high and low-temperature properties of WRMA mixtures were evaluated. Additionally, the VOCs emission characteristics of WRMA mixtures were analysed . The results indicate that activated WRP has good compatibility with asphalt. The high-content of WRP can significantly enhance the high-temperature rheological properties and low temperature cracking resistance of asphalt binder, and the addition of nanometre calcium carbonate (B3) adsorbent can further enhance the physicochemical properties of asphalt binder. Moreover, compared with 70# asphalt mixture, the dynamic stability of WRMA mixture increases by about 50%, and the immersion residual stability and freeze-thaw splitting strength values increase by 6.34% and 5.98%, respectively. In addition, the B3 adsorbent can significantly reduce the VOCs emission from WRMA mixtures. The corresponding conclusions could provide guidance for the large-scale application of high-content WRMA mixtures and promote cleaner and greener products.