Asphalt oxidative ageing and excessive hardening are known causes of premature pavementcracking. Asphalt ageing occurs mainly due to the oxidation of certain functional groups inasphalt as well as the loss of the maltene phase disturbing colloidal stability and increasingmicellisation concentration. This in turn can cause large non-soluble asphaltene aggregateswhich are typically suspended in the maltene solution and are stabilised by resin molecules toflocculate. Flocculation can cause the asphalt to become stiffer and more brittle. It should benoted that excessive hardening and brittleness of asphalt caused by oxidation during pavementproduction and service life increase the susceptibility of asphalt pavements to cracking. Therefore,reducing the extent of asphalt oxidation could increase pavement service life. Therefore,it is imperative to reduce/delay asphalt oxidation in asphalt binder. There have been severalstudies on delaying asphalt oxidation by introducing modifiers and anti-ageing additives. Furfural,an organic compound derived from a variety of agricultural by-products, has been shownto be a promising modifier for petroleum asphalt binders used in asphalt pavement. Accordingly,this paper investigates the effect of introducing furfural as an antioxidant for asphalt byevaluating the extent of oxidation ageing in asphalt specimens modified by 1%, 2% and 5%furfural. To do so, furfural was introduced to asphalt and the level of change in physiochemicaland rheological properties of asphalt after specimens were exposed to short- and long-termageing was examined. Accordingly, performance characteristics of the base asphalt were comparedwith those of furfural-modified asphalts using a rotational viscometer, Fourier transforminfrared spectroscopy and a dynamic shear rheometer to evaluate the rheological properties ofasphalt modified with furfural at different percentages. The study results showed that the additionof furfural helped reduce the extent of oxidative ageing while enhancing high-temperatureperformance of asphalt binder. Specifically, it was found that the 2% furfural modification hadthe lowest ageing index after ageing, indicating an improvement in binder oxidative ageing
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