Reacted and Activated Rubber (RAR)-Modified Dense-Graded Asphalt Mixtures: Design and Performance Evaluation

Download or read book Reacted and Activated Rubber (RAR)-Modified Dense-Graded Asphalt Mixtures: Design and Performance Evaluation written by Sampat Kedarisetty and published by . This book was released on 2018 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The modification of asphalt mixtures with rubber in the conventional process includes specialized equipment for mixing and storage and concurrently necessitates reheating prior to use. Reacted and Activated Rubber (RAR) is a novel rubber-based asphalt mixture modifier that can be added into the mixture matrix without the complexities associated with wet mixing. The objective of this study was to design and assess the performance of RAR-modified dense-graded asphalt mixtures against key pavement distresses. Furthermore, the performance of RAR-modified mixtures was compared to the unmodified and commercially available rubber-modified asphalt-based mixtures. Two levels of RAR dosage at 2 and 4 % by total weight of mix were included with two different base binders. Four performance characteristics were analyzed: resistance to rutting at high temperatures, failure by fatigue, fracture energy, and susceptibility to moisture damage. Increased rut resistance and higher fatigue lives were observed for higher RAR contents. Statistical analyses revealed insignificant changes in fracture energy among the different mixtures, and all the mixtures were found to be resistant to moisture damage. RAR was concluded as a compatible promising rubber modifier with a significant potential to improve resistance of asphalt pavements against distresses and capable of providing extended life cycles. Because RAR showed significant improvement in the performance of the dense-graded asphalt mixtures, this study recommended expanding the scope of utilizing the RAR materials with other aggregate gradations both at the laboratory and field levels in future.