Influence of High RAP on Binder Properties in Hot Mix Asphalt of Northeast

Download or read book Influence of High RAP on Binder Properties in Hot Mix Asphalt of Northeast written by Donatas Zvirblis and published by . This book was released on 2014 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impact of recycled asphalt pavement (RAP) materials on pavement performance is an important topic of study in the asphalt industry due to environmental and cost benefits. A major issue with RAP is that many agencies are still reluctant to allow producers to use more than 10 to 20 percent RAP because of concerns that mixtures with higher RAP contents will be too stiff, less workable and prone to field failures. However, the recent increases in the cost of asphalt binder and the shrinking supplies of quality aggregate has made the use of higher RAP content in hot mix asphalt (HMA) mixtures a priority for the industry. In this study, eighteen plant produced mixtures were obtained from three locations in the Northeast: New York, New Hampshire and Vermont. These mixtures were produced using different RAP contents of 0%, 20%, 30% and 40%. The eighteen mixtures were carefully extracted using American Association of State Highway and Transportation (AASHTO) T164 method "A" using trichloroethyleneand recovered with AASHTO T170 procedure. The recovered binder was then tested using Direct Shear Rheometer (DSR) and Bending Beam Rheometer (BBR) with AASHTO T315 and T313 procedures respectively. The results obtained from these tests were used to determine the continuous grade of the binders. They were then analyzed and compared to one another. Master curves were created for each recovered binder with RHEA and the data obtained from DSR frequency sweet sequence with a 4mm plate. The data recovered from master curves were used to plot black space and, crossover frequency and R-value graphs to show age hardening of binder. This paper investigates the influence of high RAP on asphalt binder stiffness and ductility.