Effect of Asphalt Rejuvenating Agent on Rutting and Creep Performance of Reclaimed Asphalt Pavement

The necessity for cost-effective and more sustainable replacements for virgin paving materials is becoming more pressing in recent years especially with the asphalt binder and aggregate economics and obligations for using greener alternatives. Hot in-place recycling (HIR) is a process that preserves or maintains distressed asphalt pavements while minimizing the use of virgin binder and aggregates. The final quality of HIR mixture depends on the characteristics of the original binder, aging during service, and new binder or the asphalt rejuvenating agent (ARA) added. While the recycling process will make the existing asphalt binder age even further, HIR mixture should maintain desired properties for another service period. Aged asphalt binder modifications are done by adding an ARA in the HIR process. However, there is a concern that ARA may adversely affect the qualities of new HIR pavement especially the rutting and creep performance since the ARA is known to soften the binder. In this study the effects of adding ARA were investigated on samples obtained from three HIR projects in Kansas. The HIR mixture performance in rutting and creep, with and without ARA, was studied by conducting flow number tests.