Composition and road performance of degraded rubber asphalt

Micro-nano rubber asphalt was prepared by high-temperature and high-speed shearing with micro-nano degraded rubber powder as raw material, and the micromorphology of micro-nano degraded rubber powder and miscible process of micro-nano rubber rubber and substrate asphalt were investigated by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectrometer, and the road performance of micro-nano rubber asphalt mixture including water stability, temperature stability and cracking failure resistance were studied by the design of asphalt aggregate ratio. In addition, the application effect of micro-nano rubber asphalt mixture in practical road engineering was further evaluated. The results showed that mass fraction of sol in degraded rubber in which the size of dissociated carbon black was about 200 nm reached 65.7%, and the interaction of sulfur cross-linked bond between degraded rubber and asphalt appeared during the miscible process; the micro-nano rubber asphalt mixture showed excellent water stability, high- and low-temperature stability and cracking failure resistance; the key technical indexes of the upper layer and the lower layer in full-depth rubber asphalt pavement of test section of Jiuquan-Jiayuguan ring expressway prepared by using micro-nano rubber asphalt mixture in Gansu province all complied with the specifications and design requirements.