Rheological and chemical characteristics of asphalt binders recycled using different recycling agents

摘要

The incorporation of reclaimed asphalt pavement (RAP) in the construction of new asphalt pavement is limited due to issues with the short-term and long-term performance of pavement. To enhance the aged binder properties, recycling agents (RAs) are added to RAP mixtures. There are different RAs available, and they impact the asphalt binder properties differently, resulting in various aging rates of recycled asphalt. Therefore, in this study, the rheological and chemical characteristics of 100% recycled asphalt binder using different RAs were investigated using Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), and Fourier-Transform Infrared Spectroscopy Attenuated Total Reflection (FTIR-ATR). The Rolling Thin-Film Oven (RTFO) and Pressure Aging Vessel (PAV) were used to simulate the short-term and long-term aging of asphalt binder, respectively. The long-term aging of the binder was simulated by aging asphalt binder with two PAV cycles. This study aims to identify the proper RA for the recycling of binders according to the aging rate, and the short- and long-term performance of recycled asphalt binder. The results show that the recycled binders with a specific RA that have the minimum initial concentration of sulfoxide and carbonyl could provide better performance in compared to recycled binders with other RAs. This result can be used to predict the long-term performance of recycled asphalt, in addition to identifying the proper RA in the recycling process of asphalt pavement. (C) 2019 Elsevier Ltd. All rights reserved.