Rheological and chemical investigation on asphalt binder incorporating high recycled asphalt with waste cooking oil as rejuvenator

摘要

Recycled asphalt pavement (RAP) and waste cooking oil (WCO) are classes of solid wastes, which have significant environmental implications. Although RAP is being used in asphalt pavements to a certain extent, the usage of high RAP content poses several challenges, which can be addressed by using WCO as a rejuvenator. The optimum combination of two materials will significantly reduce the environmental impact and may address solid waste utilization. This study conducted rheological and chemical investigations on crumb rubber-modified asphalt binder with high RAP content using WCO as a rejuvenator. The crumb rubber-modified binder was chosen in this study as past studies mostly concentrated on unmodified binders. Three concentrations of WCO, such as 5.0, 7.5, and 10% by weight of the total binder, were mixed with the 50 and 60% RAP binder content to find the optimum WCO dose. The rheological tests indicated that asphalt binder with 50% RAP + 5.0% WCO and 60% RAP + 7.5% WCO depicted properties similar to the virgin binder. The fatigue performance of binders with 50 and 60% RAP was significantly better than long-term aged binders. The stripping test of asphalt indicates a slightly higher stripping in binders with RAP compared to the virgin binder. The thermogravimetry analysis revealed the binders had similar thermal stability and mass loss. The Fourier transform infrared spectroscopy (FTIR) indicated a lower presence of aliphatic hydrocarbons and higher aromatics content in the RAP binder modified with WCO. This can be mainly attributed to the peptizing power of WCO.