Adopting Viscosity Grading System for Proper Selection of Paving Asphalt in Sudan

Magdi M. E. Zumrawi

Abstract: Selection of proper asphalt binder is one of the most important factors considered in asphalt mixture design. This paper is aimed to -overview the important role of adopting the viscosity grading system in performance and durability of flexible pavements in Sudan. The -literature of the traditional grading systems with their respective advantages and disadvantages is intensively reviewed. An effort is made -to verify the viscosity grading system is more realistic, reliable and practical than the old penetration grade. Twenty samples of asphalt -cement, selected from penetration grades 60/70 and 85/100, were subjected to laboratory testing for measuring their consistency and -safety properties. The results revealed that asphalt binders, from different sources used in the industry are highly temperature susceptible, -though they have complied with the standards. Recommendations have been made to implement the viscosity grading system in order to -improve the quality, performance and durability of bituminous pavements in Sudan. -

Keywords: Viscosity, penetration, grading, asphalt, temperature -