Effect of DLTDP and furfural on asphalt binders: Optimal dosage and PG grading
Ingrid Camargo, Bernhard Hofko, Johannes Mirwald
Abstract
The addition of anti-aging additives to asphalt binders has increased drastically over the last decade. Two candidates, dilauryl thiodipropionate (DLTDP) and furfural have been highlighted in some recent studies, as they showed promising results. However, the determination of the optimal content of each one of the compounds still needs to be better elaborated. In this matter, a new method for the dosage of furfural and DLTDP, based on the minimum rheological aging index, is presented in this paper. In addition, the Superpave asphalt binder characterization is used to investigate the effect of the anti-aging compound additives (composed by furfural and DLTDP) on the high, intermediate, and low temperatures of two asphalt binders. The achieved results reveal that furfural is partially lost during the short-term and long-term aging due to the high temperatures considered during each aging procedure. This demonstrates that the use of furfural may not be suitable for the preparation of hot mix asphalt. In addition, the combination of DLTDP and furfural (at the obtained optimal contents, for each binder) leads to a softening of the binders and a decrease of the continuous PG span. Thus, the combined use of these additives as anti-aging agents could not be proved by this study.