A review on the crumb rubber-modified asphalt in the Middle East

The asphalt pavement in the Middle East suffers from numerous problems, such as high traffic load, critical climate changes, poor construction quality, and economic problems. These reasons drove researchers to develop modified asphalt binders with excellent performances at a relatively lower cost. Crumb rubber (CR) still has in its early stages in the Middle East countries as an asphalt modifier. The objective of this review is to understand the effect of CR on the performance of asphalt binder and asphalt mixture used in the Middle East countries. The application of CR through the wet process improved the rutting, cracking, and aging resistance of the asphalt mixture. The combination of CR and other materials, such as Styrene–Butadiene–Styrene and Reclaimed Asphalt Pavement, further enhanced the properties of rubberized asphalt. It can be concluded that pavement implemented with rubberized asphalt technology is promising in the Middle East, as it is much more effective than conventional asphalt or other polymer-modified asphalt. For future study, the elasticity modulus and tensile strength of rubberized asphalt in the Middle East are recommended, and the durability of constructed pavement using CR should be evaluated.