COOEE has shown that asphalt mixtures can be optimized to reduce rolling resistance properties, but durability must be validated in order to make applications realistic.
At the micro-scale level the rheological response of the mortar of the asphalt mixtures will be studied with the aim of arriving at a rheological characterization of the bitumen filler. The interaction of mastic components that includes bitumen, fillers, and polymer, will be investigated in relation to different temperatures, aging, and moisture levels. Input from WP2 is crucial here to understand how polymer additives and water affect aging.
Through meso-scale simulation of shear and tensile stresses generated by the tires on the aggregate- mortar system, the performance and stability of the texture can be studied (Feng et al., 2015a, 2015b). At the macro-scale, the accelerated-pavement-test facility available at the DRD will be used to validate the model. Road test sections are an important part of WP3.