Novel Methodology to Investigate and Obtain a Complete Blend between RAP and Virgin Materials
Publication: Journal of Materials in Civil Engineering
Volume 30, Issue 5
Abstract
Pavement engineers are continually attempting to resolve the problems associated with the disposal of highway construction materials and conserve the natural resources in line with producing a more economically and environmentally friendly asphalt mixture. This study presents a novel methodology to investigate and obtain a complete blending in the laboratory using a nanomechanical approach so that designers can be more confident in estimating the performance of asphalt mixtures incorporating reclaimed asphalt pavement (RAP) materials. The study also presents an effect of warm additives, Sasobit and Rediset LQ, on the level of blending between RAP and virgin materials. Images obtained from nanoindentation were validated using a scanning electron microscope (SEM), while the level of blending was linked to the overall fatigue cracking of asphalt mixtures, which was measured using dynamic shear rheometer (DSR). It was revealed that although Rediset LQ improved the fatigue life and nanomechanical properties of the virgin interfacial transition zone (ITZ) and mastic phases, it has no effect on the diffusion of virgin binder into aged binder (binder surrounding RAP aggregate) or rejuvenating of aged binder, whereas Sasobit decreased the viscosity of binder and has a great influence in accelerating complete blending between RAP and virgin materials. In summary, nanoindentation integrated with an optical microscopy is a powerful technique to investigate and obtain complete blending between RAP and virgin materials.
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Acknowledgments
The authors would like to acknowledge the Iraqi government represented by the Iraqi Ministry of Higher Education and Scientific Research and Iraqi Cultural Attaché in London for sponsoring the current project, and Dr. Tim Joyce (School of Engineering) for assisting with the SEM testing. They would also like to thank all the materials suppliers. Especial thanks must also go to the geologist, Mr. John Kavanagh, Geology Department at the University of Liverpool.
References
AASHTO. (2005). “Standard practice for superpave volumetric mix design.” AASHTO M323, Washington, DC.
Al-Qadi, I. L., Elseifi, M., and Carpenter, S. H. (2007). “Reclaimed asphalt pavement—A literature review.”, Illinois Center for Transportation, Springfield, IL.
Bonaquist, R. (2008). “Mix design practices for warm mix.”, National Cooperative Highway Research Program, Washington, DC.
Bowers, B. F., Moore, J., Huang, B., and Shu, X. (2014). “Blending efficiency of reclaimed asphalt pavement: An approach utilizing rheological properties and molecular weight distributions.” Fuel, 135(Nov), 63–68.
BSI (British Standards Institution). (2005). “Hot rolled asphalt for roads and other paved areas, in specification for constituent materials and asphalt mixtures.” BS EN 597-1, London.
BSI (British Standards Institution). (2012). “Bituminous mixtures. Test methods for hot mix asphalt: Determination of bulk density of bituminous specimens.” BS EN 12697-6, London.
Eddhahak-Ouni, A., et al. (2012). “Experimental investigation of the homogeneity of the blended binder of a high rate recycled asphalt.” Road Mater. Pavement Des., 13(3), 566–575.
Hanson. (2016). “Sustainability summary report.” ⟨http://www.hanson-sustainability.co.uk/sites/default/files/assets/document/hanson-sustainability-report-2016.pdf⟩ (Aug. 26, 2016).
Huang, B., Kingery, W., and Zhang, Z. (2004a). “Laboratory study of fatigue characteristics of HMA mixtures containing RAP.” Int. Symp. on Design and Construction of Long Lasting Asphalt Pavements, Transportation Research Board, Washington, DC.
Huang, B., Li, G., Vukosavljevic, D., Shu, X., and Egan, B. K. (2005). “Laboratory investigation of mixing hot-mix asphalt with reclaimed asphalt pavement.” Transp. Res. Rec., 1929, 37–45.
Huang, B., Zhang, Z., and Kinger, W. (2004b). “Fatigue crack characteristics of HMA mixtures containing RAP.” Proc., 5th Int. RILEM Conf. on Reflective Cracking in Pavements, RILEM, Paris, 631–638.
Huang, Y., Bird, R. N., and Heidrich, O. (2007). “A review of the use of recycled solid waste materials in asphalt pavements.” Resour. Conserv. Recycl., 52(1), 58–73.
Jamshidi, A., Hamzah, M. O., and You, Z. (2013). “Performance of warm mix asphalt containing Sasobit®: State-of-the-art.” Constr. Build. Mater., 38(Jan), 530–553.
Karlsson, R., and Isacsson, U. (2006). “Material-related aspects of asphalt recycling—State-of-the-art.” J. Mater. Civ. Eng., 81–92.
Kriz, P., et al. (2014). “Blending and diffusion of reclaimed asphalt pavement and virgin asphalt binders.” Road Mater. Pavement Des., 15(S1), 78–112.
Lee, J. C., Edil, T. B., Tinjum, J. M., and Benson, C. H. (2010). “Quantitative assessment of environmental and economic benefits of recycled materials in highway construction.” Transp. Res. Rec., 2158, 138–142.
McDaniel, R. S., Soleymani, H., Anderson, R. M., Turner, P., and Peterson, R. (2000). “Recommended use of reclaimed asphalt pavement in the Superpave mix design method.”, National Cooperative Highway Research Program, Washington, DC, 30.
Mohajeri, M., Molenaar, A., and Van De Ven, M. (2012). “Cracking resistance of recycled asphalt mixtures in relation to blending of RA and virgin binder.” 7th RILEM Int. Conf. on Cracking in Pavements, Springer, New York, 1311–1321.
Nahar, S., Mohajeri, M., Schmets, A. J., Scarpas, A., Van De Ven, M. F., and Schitter, G. (2013). “First observation of blending-zone morphology at interface of reclaimed asphalt binder and virgin bitumen.” Transp. Res. Rec., 2370, 1–9.
NAPA (National Asphalt Pavement Association). (2009). “Black and green: Sustainable asphalt, now and tomorrow.” Lanham, MD.
Nguyen, V. H. (2009). “Effects of laboratory mixing methods and rap materials on performance of hot recycled asphalt mixtures.” Ph.D. thesis, Univ. of Nottingham, Nottingham, U.K.
Oliver, J. W. (2001). “The influence of the binder in rap on recycled asphalt properties.” Road Mater. Pavement Des., 2(3), 311–325.
Oliver, W. C., and Pharr, G. M. (1992). “An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments.” J. Mater. Res., 7(6), 1564–1583.
Rad, F., Sefidmazgi, N., and Bahia, H. (2014). “Application of diffusion mechanism: Degree of blending between fresh and recycled asphalt pavement binder in dynamic shear rheometer.” Transp. Res. Rec., 2444, 71–77.
Roberts, F. L., Kandhal, P. S., Brown, E. R., Lee, D.-Y., and Kennedy, T. W. (1996). Hot mix asphalt materials, mixture design and construction, National Asphalt Pavement Association Educational Foundation, Lanham, MD.
Shen, J., Amirkhanian, S., and Aune Miller, J. (2007a). “Effects of rejuvenating agents on Superpave mixtures containing reclaimed asphalt pavement.” J. Mater. Civ. Eng., 376–384.
Shen, J., Amirkhanian, S. N., and Lee, S. J. (2007b). “HP-GPC characterization of rejuvenated aged CRM binders.” J. Mater. Civ. Eng., 515–522.
Stephens, J. E., Mahoney, J., and Dippold, C. (2001). “Determination of the PG binder grade to use in a RAP mix.”, Connecticut Dept. of Transportation, Newington, CT.
Zaumanis, M., and Mallick, R. B. (2015). “Review of very high-content reclaimed asphalt use in plant-produced pavements: State of the art.” Int. J. Pavement Eng., 16(1), 39–55.
Zaumanis, M., Mallick, R. B., and Frank, R. (2014). “100% recycled hot mix asphalt: A review and analysis.” Resour. Conserv. Recycl., 92(Nov), 230–245.
Zhao, S., Huang, B., Shu, X., and Woods, M. E. (2015). “Quantitative characterization of binder blending: How much recycled binder is mobilized during mixing?” Transp. Res. Rec., 2506, 72–80.
Information & Authors
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Published In
Journal of Materials in Civil Engineering
Volume 30 • Issue 5 • May 2018
Copyright
©2018 American Society of Civil Engineers.
History
Received: May 11, 2017
Accepted: Oct 6, 2017
Published online: Feb 16, 2018
Published in print: May 1, 2018
Discussion open until: Jul 16, 2018
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