Sulphur utilization in asphaltic concrete pavements

Used as the primary binder in asphaltic concrete production, the high financial costs of bitumen, coupled with the constricting amounts needed, have forced pavement engineers to search for an alternative material that can at least partially be used as a substitute. The relative abundance, accessibility, low cost, and environmental compatibility of sulphur has made it a preferable alternative. A considerable amount of conventional bitumen, typically 20 to 40 percent by weight, can be replaced by sulphur to generate sulphur-extended pavements (SEP). The extensive laboratory, field, and analytical investigations conducted on several sulphur-extended pavements (SEP) have led to its consideration as a feasible alternative to the ordinary asphalt-concrete pavements (ACP). The deep interest shown in SEP in the 1970s resulted in its increased utilization, especially in North America, Canada, Europe, and the Middle East. Although many studies on this topic were conducted in the past, its abundance in natural reservoirs, along with its current oversupply from sour natural gas, oil sands, and refineries, have combined to again draw the interest of pavement engineers in the use of sulphur. The aim of this paper is thus to present an in-depth and integrated study relative to sulphur utilization in asphaltic concrete pavement.