Investigation of the rheological properties of devulcanized rubber-modified asphalt with different rubber devulcanization degrees and rubber contents

Abstract

Devulcanized rubber-modified asphalt (DRMA) possesses broad application potential due to its environmental friendliness and exceptional performance. However, the relationship between the rubber devulcanization degree, rubber content, and the modification effect of asphalt binder has not been clearly revealed. In this work, DRMA with different rubber devulcanization degrees and contents was prepared. The storage stability and rheological properties of several asphalt binders were evaluated, and the interaction mechanism between different devulcanized rubber (DVR) and asphalt was also detected. The storage stability of DRMA increased with the rubber devulcanization degree and decreased with the DVR content. The rheological test results demonstrated that under the same rubber devulcanization conditions, the elasticity ratio, rutting resistance, and fatigue resistance of the ML40 series was enhanced continuously, while the above properties of DRMA of the other series were enhanced and then weakened with the rubber devulcanization degree. Additionally, the DRMA of the ML60 series had a superior elasticity ratio and rutting resistance when the DVR content was the same. The low-temperature performance of DRMA increases with the rubber devulcanization degree and DVR content.