Use of Rejuvenators for Production of Sustainable High Content RAP Hot Mix Asphalt

The XXVIII International Baltic Road Conference: Proceedings 2013
Mārtiņš Zaumanis, Rajib B. Mallick, Robert Frank

Aged binder is the main obstacle for increasing the use or Reclaimed Asphalt Pavement (RAP) in production of asphalt pavements. RAP binder is much stiffer and therefore high RAP content mixes are perceived to be susceptible to fatigue and thermal cracking failures. Appropriate choice of rejuvenator may allow reducing the binder viscosity to attain the desired mixture workability and recover the necessary performance properties of the aged binder. Six differently originated rejuvenators were added to extracted binder at 12% dose including aromatic extract, waste engine oil, tall oil, organic oil, waste vegetable oil and waste vegetable grease. The rejuvenation potential of these products was evaluated by performing multiple empirical as well as performance tests and the results compared with a virgin binder. The rejuvenators proved to soften the extracted binder to the level of virgin and the kinematic viscosity results show that the optimum compaction temperature can be reduced by 15°C to 25°C compared to extracted binder. Performance Grade (PG) test results showed that none of the rejuvenators reduced the high PG of extracted binder to the level of virgin binder indicating increased rutting resistance. At the same time most are able to reduce low PG from -12°C of the extracted binder to at least the required -22°C. The low temperature performance correlated well with penetration index, proving that thermal cracking should not be an issue at appropriate rejuvenator dose. The binder fatigue performance was evaluated through Linear Amplitude Sweep (LAS) test. Only waste vegetable products were able to increase the fatigue resistance to the level of virgin binder at a 12% dose using LAS test while the Superpave G*·sinδ indicated that all rejuvenators pass the minimum fatigue requirement.

Keywords
Rejuvenators, softening agents, waste vegetable oil, linear amplitude sweep test.
Hyperlink
http://www.balticroads.org/downloads/28BRC/051_T03.pdf

Zaumanis, M., Mallick, R., Frank, R. Use of Rejuvenators for Production of Sustainable High Content RAP Hot Mix Asphalt. In: The XXVIII International Baltic Road Conference: Proceedings, Lithuania, Vilnius, 26-28 August, 2013. Vilnius: Baltic Road Association, 2013, pp.1-10. ISBN 9786099552606.

Publication language
English (en)