Laboratory Evaluation of Deurex-Modified Asphalt

The ability of Deurex natural sugar cane wax to reduce the blending and compaction temperatures of warm-mix asphalt renders it a promising technology in pavement construction to reduce ${\mathrm{CO}}_2$ emissions and save energy. This new warm-mix additive might revolutionize pavement construction and warm-mix asphalt production by introducing a new class of mixtures with excellent environmental performance. The goal of this study was to evaluate the feasibilities and benefits of the incorporation of Deurex into asphalt binders. Deurex was blended into asphalt at contents of 1, 3, 5, and 7%, and the following tests were performed: physical properties, performance grade, multiple stress creep recovery, frequency sweep, separation, differential scanning calorimetry (DSC), and Fourier transform infrared rheometer (FTIR). The test results showed that the increase in Deurex significantly reduces the viscosity of asphalt binders, implying that a decrease in the blending and compaction temperatures of asphalt mixtures can be achieved during pavement construction. In addition, the tests showed that the addition of Deurex increases complex modulus ($G^{*}$), rutting factor ($G^{*}/\sin \delta$), average percentage recovery, and phase angle, and reduces nonrecoverable creep compliance and phase angle. It is suggested that Deurex-modified binders are less subject to permanent deformation at high temperature. Moreover, DSC analyses showed that Deurex has little effect on asphalt thermal properties. Further, FTIR analyses showed that chemical reactions might happen during the mixing of Deurex and asphalt. Overall, the good performance of Deurex-modified asphalt showed its potential as a new additive in warm-mix asphalt manufacture.