Cracking Resistance of Recycled Asphalt Mixtures in Relation to Blending of RA and Virgin Binder

  • M. Mohajeri
  • A. A. A. Molenaar
  • M. F. C. Van de Ven
Part of the RILEM Bookseries book series (RILEM, volume 4)


The degree of blending between the reclaimed asphalt (RA) binder and the virgin bitumen during the asphalt recycling mixing process is presumed to greatly influence the performance properties of recycled asphalt mixtures. Studies on the effect of different mixing methods using different quantities of RA in the laboratory, showed that tensile strength of RA mixtures and their fatigue characteristics are affected to some extent by the preheating conditions and moisture content of the RA The effects however are not very significant. These somewhat unexpected results are believed to be due to the low void content of the mixtures tested but they also might be influenced by the amount of blending that has taken place between the RA binder and the virgin binder.

This paper will report on how well the virgin binder blends with the old binder which is part of the RA. It is believed that by knowing precisely the degree of blending of RA binders, one can develop much more realistic mix designs and modify or select better mixing processes. This will result in more durable pavements.

Nano-indentation is employed to measure the mechanical properties of the binder layer and to determine the degree of blending between the hard RAbinder and the soft virgin binder. Also the characteristics of the interface zone between binder and aggregate were measured in this way. For this purpose mono sized sea sand particles and glass beads up to 4mm were mixed with a virgin soft and hard bitumen separately to produce different mixtures in order to simulate different levels of blending and interface properties. RA was simulated by mixing aggregate with hard bitumen. Nano-indentation was employed to determine the resilient modulus and hardness at each location and these results were used to determine the degree of blending.

Although current reported nanoindentation results in this paper didn’t allow to determine blending degree between two binders; further nanoindentations will be performed on differnt types of samples to analyze the degree of blending.


Resilient Modulus Indirect Tensile Strength Partial Warming Virgin Aggregate Binder Zone 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    McDaniel, R.S., Soleymani, H., Anderson, R.M., Turner, P., Peterson, R.: NCHRP Final Report (9-12), TRB, Washington D.C. (2000)Google Scholar
  2. 2.
    Oliver, J.W.H.: Int. Road. Mat. Pav. Design 2(3), 311–325 (2001)Google Scholar
  3. 3.
    Stephens, J.E., Mahoney, J., Dippold, C.: Connecticut Department of Transportation, No. JHR 00-278 (2001)Google Scholar
  4. 4.
    Huang, B., Li, G., Vukosavljevic, D., Shu, X., Egan, B.: Transportation Research Report (1929), p. 37–45 (2005)Google Scholar
  5. 5.
    Carpenter, S.H., Wolosick, J.R.: J. Transportation Research Record 777, pp. 15–22. TRB, Washington, D.C (1980)Google Scholar
  6. 6.
    Huang, B., Zhang, Z., Kingery, W., Zuo, G.: Cracking in Pavements. In: Proceedings of the 5th International RILEM, pp. 631–650 (2004)Google Scholar
  7. 7.
    Al-Qadi, I.L., Carpenter, S.H., Roberts, G., Ozer, H., Aurangzeb, Q.: Research report of Illinois Center for Transportation. No. ICT-R27-11 (2009)Google Scholar
  8. 8.
    Bennert, T., Dongre, R.: J. Tran. Res. Board, 1, 75–84 (2010)Google Scholar
  9. 9.
    Parashant, S., Mehta, Y.A., Nolan, A.: In: Proceeding of Transportation Research Board, 89th Annual Meeting, n.10- 0917 (2010)Google Scholar
  10. 10.
    Noureldin, A.S., Wood, L.E.: J. Tran. Research Record 1115, 51–61 (1987)Google Scholar
  11. 11.
    Karlsson, R., Isacsson, U.: In: Proceedings of 72nd AAPT Annual Meeting, vol. 72, pp. 563–606 (2003)Google Scholar
  12. 12.
    Karlsson, R., Isacsson, U.: J. Material Science 38, 2835–2844 (2003)CrossRefGoogle Scholar
  13. 13.
    Read, J., Whiteoak, D.: The shell Bitumen Handbook, pp. 29–37. Shell bitumen, London (2003)Google Scholar

Copyright information

© RILEM 2012 2012

Authors and Affiliations

  • M. Mohajeri
    • 1
  • A. A. A. Molenaar
    • 1
  • M. F. C. Van de Ven
    • 1
  1. 1.Road and Railway Engineering SectionDelft University of TechnologyDelftThe Netherlands

Personalised recommendations