Effect of mixing technology on hot asphaltic mixtures properties

The optimum utilization of asphaltic concrete mixtures for highway andairport structures must start with complete understanding of their engineering properties and their resistance to major distress modes.This study is primarily concerned with developing a laboratory basedprocedure for asphaltic concrete mixtures characterization. This procedure is used in evaluating various mixtures produced by using ntraditional (UTR)mixing technologies with that produced by using the traditional (TR) mixingtechnology. Engineering properties, such as stiffness modulus, tensile strength, Poisson’s ratio, tensile strain, compressive strength and modulus of rupture of the different mixtures over the service temperature range of 20°C to 60°C are measured and evaluated. Mixtures are also evaluated against their resistance tomajor distress modes, such as rutting and fatigue cracking. Durability in terms of the effects of moisture amage, age hardening, and thermocycling on their strength values are taken into consideration.A comparison between the results of Marshall test and unconfinedcompression test as well as a comparison between measured stiffness moduli (Smix) and those calculated from Heukelorn method, are conducted.Furthermore, the rheological properties of filler-asphalt pastes withdifferent types of filler at various filler / asphalt (F/A) ratios are alsoinvestigated in this study.The findings of this study indicate that the major advantage of using UTRmixing technologies is the production of homogenous mixtures of lowersusceptibility of stiffness, tensile strength, compressive strength and rupture