Abstract
Waste cooking oils (WCOs) show promise as a rejuvenator for reclaimed asphalt pavement (RAP) binders. Their use helps to make RAP a renewable resource and to address environmental concerns related to WCO disposal. While studies suggest that 100% RAP for pavement is feasible, RAP will likely be combined with a virgin binder and aggregate incrementally in the field. In this study, the rheological properties of the virgin binder blended with a simulated RAP binder and 10% waste vegetable oil (WVO) as a rejuvenator were examined. Viscosities below that of a PG 64-22 virgin binder were observed with WVO in blends of 40 or 60% RAP and the virgin binder. The virgin-60% RAP/WVO binder blend retained a Superpave grade of the virgin binder and was found to satisfy requirements for both rutting parameter and fatigue resistance. Results indicated that WVO significantly reduced the effects of long-term ageing, making the blend containing RAP durable. The effect of RAP content on WVO/virgin binder blends was most pronounced on the rutting parameter. A “molecular lubrication” model is suggested as a mechanism for the viscosity reduction with WVO.
Highlights
Transportation contributes to the functioning of societies in many ways, with significant economic impact through its roles in commerce and with a higher quality of life for citizens as a result of greater mobility
Rheological properties from dynamic shear rheometer (DSR) tests serve as an indicator of rutting and cracking performance of the binder, when used in an asphalt mix, whereas viscosity reflects the coatability of asphalt binder on aggregate at the hot mix asphalt (HMA) plant
The addition of waste vegetable oil (WVO) reduced the viscosity of reclaimed asphalt pavement (RAP) binder blends (40 or 60%) to values below that of the virgin binder
Summary
Transportation contributes to the functioning of societies in many ways, with significant economic impact through its roles in commerce and with a higher quality of life for citizens as a result of greater mobility. With over 80% of highways in the world covered with asphalt pavement[1] and annual demand for the asphalt binder on the order of 100 million tons,[2] the potential gains from recycling toward sustainability are tremendous. With significant savings from asphalt binder and aggregate reuse, as well as the costs associated with hauling new materials to a construction site and carrying wastes away for disposal. It has been estimated that the overall cost can be reduced by half or more using 100% reclaimed asphalt pavement (RAP).[3] The asphalt binder represents a large fraction of these potential savings. A trend since 2000 of rapidly increasing asphalt binder cost coupled with price volatility and a broader awareness of the need for sustainability has created a growing desire to increase the usage of RAP by state departments of transportation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
