Improvement of RAP Binder Mobilization and Blending Efficiency Using Microwave Induction

Abstract

The mobilization of aged asphalt and the blending of aged and virgin asphalt are the keys to realize the high value of reclaimed asphalt pavement (RAP) in recycled asphalt mixtures, and the high performance of recycled asphalt mixtures. Microwave induction technology is used in this study to improve the mobilization aged asphalt and the blending efficiency of aged and virgin asphalt. A migration test, Fourier transform infrared spectroscopy (FTIR), and surface free energy (SFE) test were used as assessment tools. The results indicated that microwave induction can enhance the mobilization of RAP binder and the blending efficiency of aged and virgin binders. Microwave induction also overcomes the problem of low efficiency due to the outside-in energy transmission mode and secondary aging caused by the traditional heating method. This study reveals that the utilization of microwave heating in producing RAP asphalt mixtures can improve the RAP content and technical performance of a recycled asphalt mixture, and comprehensively promote the recycling of asphalt.