Comparative evaluation of hot-mix asphalt design methods

This study was done to evaluate superior performing asphalt pavements (Superpave) mixture design using local materials in Malaysia. Comparison was also done with the conventional Marshall method-designed mixture conforming to the specifications of the Malaysia Public Works Department (PWD). The experimental plan consisted of a matrix involving one granite aggregate source, two different aggregate gradation and two different asphalt binder types. Local granite aggregates being produced presently were found to conform to the consensus and source aggregate properties criteria of the Superpave mixture design system. Mixture volumetric properties showed that Superpave-designed mixture uses less asphalt binder than the PWD Marshall mixture. Rutting and moisture susceptibility tests showed that Superpave-designed mixtures are more resistant to rutting and moisture damage compared with the PWD mixture. Mixture characterisation tests showed that Superpave mixtures have higher stiffness than the PWD mixture. These indicate that Superpave-designed mixtures are superior to the PWD Marshall-designed mixture.