Optimizing the Effective Use of Reclaimed Asphalt Pavement in Local Roadways

Abstract

This study involved the construction of eight test sections in the City of Columbus, Ohio, to evaluate the effects of using different reclaimed asphalt pavement (RAP) contents and types of rejuvenator on the performance and properties of asphalt mixes used for local roads. The first section (control section) had a mix with 20% RAP and PG 64-22 binder. While three sections had mixes with 30%, 40%, 50% RAP, PG 64-22 binder, and Sylvaroad rejuvenator (tall oil), three other sections had mixes with the same RAP percentages and binder but used Hydrolene (aromatic extract) as the rejuvenator. Finally, the last test section was constructed using a mix with a 30% RAP and PG 64-28 binder (softer binder). Specimens were compacted in the laboratory from loose mixes that were obtained during the construction of each test section. Laboratory tests were conducted to evaluate the resistance of the prepared samples to moderate-temperature cracking, low-temperature cracking, rutting, and moisture damage. The test results showed that Hydrolene was more effective than Sylvaroad in improving the moderate-temperature cracking resistance of RAP mixes with more than 30% RAP. In addition, the tests results showed that the 30% RAP, 40% RAP, and 50% RAP mixes had similar low-temperature cracking resistance to that of the control. The laboratory test results also showed that mixes with 30% and 40% RAP had acceptable resistance to moisture damage. Furthermore, all mixes had acceptable rutting resistance. Finally, preliminary field evaluation showed that there were no observed distresses in the test sections after 7 months of construction.