Determining Optimum Sulfur Content as Alternative Binder Additive in Asphaltic Concrete Pavements

Although bitumen, the binder most commonly used in asphaltic concrete pavements, constitutes only 3 to 5% of the total mixture, it has a significant impact on the total cost of the pavement. Because of this cost factor, this paper investigates the optimal use of the very abundant sulfur as a replacement for the more expensive bitumen. In this study, bitumen-sulfur blends were prepared, using an increasing amount of sulfur as replacement, up to 50% by weight. A group of samples were then short-term and long-term aged by using the rolling thin film oven test and a pressure aging vessel. Aged and virgin samples were then further tested with Superpave binder test methods. The promising results demonstrate that the addition of sulfur not only lowers total costs, but also increases the performance of the binder.