Abstract
Roads in Iraq are performing poorly with pavement life much shorter than the expected. The high traffic intensity in terms of commercial vehicles, the serious overloading of trucks and significant variation in daily and seasonal temperature of the pavement have been responsible for early development of distress like rutting, fatigue and thermal cracking on bituminous surfacing. One of the advantages of the Marshall Mix Design method is that the performance of the mixes can be expected for local materials and environmental impact.
The Superpave mix design method differs from the Marshall Mix design methods by using performance-based and performance-related criteria to design the proper asphalt mix. This allows a direct relationship to be drawn between the lab and field performance of the asphalt mix.
This technology has a tremendous potential to be implemented in Iraq, which will pay itself with higher performance and longer lasting roads. Hence, there is need to have a comprehensive study comparing the design of bituminous mixes using both Superpave and the Marshall method of Mix Design.
The main objective of the study is the comparison between traditional Marshall Design method and the Superpave system design method in the wearing course mixes in flexible pavements. This process will be carried out by evaluating the volumetric, mechanical properties and moisture susceptibility.
