Warm Mix and Reclaimed Asphalt Pavement: A Greener Road Approach
Utilization of a high percentage of reclaimed asphalt pavement (RAP) requires higher production temperatures and consumes more energy. High production temperature expedites the aging of bitumen in RAP, which could affect the mixture performance. Warm mix asphalt (WMA) additive enables reduced production temperatures as a result of viscosity reduction. This paper evaluates the integration of a high percentage of RAP with a WMA additive known as RH-WMA. The optimum dosage of RH-WMA was determined from basic properties tests. A total of 0%, 30% and 50% RAP contents from two roads sources were modified with RH-WMA. The modified RAP bitumen were examined for viscosity, stiffness, rutting resistance and greenhouse gas emissions. The addition of RH-WMA improved the flow of bitumen by reducing the viscosity, and thus, decreased the construction temperature. The stiffness of the RAP modified bitumen reduced with the incorporation of RH-WMA. The positive improvement in rutting resistance was observed on bitumen with the addition of RAP and RH-WMA in comparison with control. It was estimated that the addition of RH-WMA could potentially reduce fuel usage and GHG emissions by 22 %. Hence, the synergy of RAP and WMA technology can be an alternative in green road construction.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.2021873Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 717
 Energy Information Administration (EIA), U.S. oil and natural gas reserves both increase in 2014, U.S. 30 November 2015. Accessed on 7 December 2015.
 A. Copeland, Reclaimed asphalt pavement in asphalt mixtures: State-of-the- practice (Report No. FHWA-HRT-11-021), Federal Highway Administration, 2011.
 A. J. D'Angelo et al., Warm-mix asphalt: European practice. No. FHWA-PL-08-007, 2008.
 R. West, J. R. Willis and M. Marasteanu, Improved mix design, evaluation, and materials management practices for hot mix asphalt with high reclaimed asphalt pavement content, NCHRP Report 752, Transportation Research Board Washington, D.C, 2013.
 P. Leandri, G. Cuciniello and M. Losa, Study of sustainable high performance bituminous mixtures, Procedia-Social and Behavioral Sciences, vol. 53, pp. 495-503, 2012.
 I. L. Al-Qadi, S. Carpenter, G. Roberts, H. Ozer, M. Elseifi and J. Trepanier, Determination of Usable Residual Asphalt Binder in RAP, Research Report No. FHWA-ICT-09-031, Federal Highway Administration, U.S. Department of Transportation and Illinois Department of Transportation, 2009.
 B. Hill, Performance evaluation of warm mix asphalt mixtures incorporating reclaimed asphalt pavement, MSc Dissertation, University of Illinois, USA, 2011.
 S. Zhao, B. Huang, X. Shu and M. Woods, Comparative evaluation of warm mix asphalt containing high percentages of reclaimed asphalt pavement, Construction and Building Materials, vol. 44, pp. 92-100, 2013.
 B. J. Putman, Investigation of warm mix asphalt (WMA) technologies and increased percentages of reclaimed asphalt pavement (RAP) in asphalt mixtures, PhD Dissertation, Clemson University, 2012.
 D. H. Timm, J.W. Richard and A. Kvasnak, Full-scale structural evaluation of fatigue characteristics in high reclaimed asphalt pavement and warm-mix asphalt, Journal of Transportation Research Board, pp. 56-63, 2011.
 A. Vargas-Nordcbeck and D. H. Timm, Rutting characterization of warm mix asphalt and high RAP mixtures, Road Materials and Pavement Design, vol. 13(SUPPL. 1), pp.1-20, 2012.
 AASHTO T315, Determining the rheological properties of asphalt binder using a Dynamic Shear Rheometer (DSR), American Association of State Highway and Transportation Officials, Washington (D.C.), 2004.
 A. J. D'Angelo, The relationship of the MSCR test to rutting, Road Materials and Pavement Design, vol. 10 (sup1), pp. 61-80, 2009.
 M.D. Domingos and A.L. Faxina, The application of the MSCR test on the rheological characterization of asphalt binders modified with EVA and PPA, International Journal of Pavements Conference, Brazil, A.L. pp. 1-12, 2013.
 Guidelines to GHGs calculation, Version1.2. Department for Environment, Food and Rural Affairs (DEFRA), 2010.
 M. O. Hamzah, A. Jamshidi A. and S. Shahadan, Effects of Sasobit® on the required heat energy and CO2 emission on blended asphalt binder incorporated with aged binder, European Journal of Scientific Research vol. 42(1), pp. 16-24, 2010.