Development of Using Crumb Rubber in Asphalt Modification: A Review

In recent decades, crumb rubber has been widely used as a sustainable and recycled material in road construction. To further promote the use of crumb rubber binder/rubber asphalt mixtures in road applications, overview its development, and investigate the requirements of using this material, this study reviewed the development, manufacture, performance, and impediments of using crumb rubber in asphalt modification. First, the development of crumb rubber binders abroad and in China was reviewed, along with the criteria of crumb rubber materials in related national/state specifications for crumb rubber binder/rubber asphalt mixtures. Then, the methods of incorporating crumb rubber into binder/mixtures were illustrated, including the dry(retained in a 1.0 mm sieve) and wet(pass through a 1.0 mm sieve) processes. The interaction reaction between crumb rubber particles and base asphalt binder was summarized. According to the literature, the effects of crumb rubber characteristics (such as crumb rubber particle sizes and crumb rubber contents) on the performance of crumb rubber binder/rubber asphalt mixtures were summarized. Finally, the impediments of using crumb rubber binder/rubber asphalt mixtures were discussed with solutions accordingly. © 2021, Editorial Department of China Journal of Highway and Transport. All right reserved.