Production of innovative, recycled and high-performance asphalt for road pavements

Abstract

The paper deals with a specific laboratory study aiming at perfectioning recycled asphalt with high mechanical performance, for surface and structural layers of flexible pavements. The aim of the research was to combine in the samematerial themaximum possible quantity of recycled asphalt (RA), coming from degraded asphalt layers, together with high structural performance of the recycled mixtures obtained (mainly stability, load spreading properties, rutting and fatigue resistance) that should not be lower, or possibly better than those offered by traditional asphalt mixture, made with virgin binder and aggregate. For this purpose, innovative recycled mixtures, close-graded and with high mechanical performance, characterized by high content of recycled asphalt (up to 50%) and designed for surface, binder and base layers were investigated in a laboratory study. The results of physical and mechanical characterization tests show that, by controlling the homogeneity of recycled material and by using new bitumen with adequate rheological properties, it is possible to obtain paving mixtures with high content of recycled materials that, in relation to their intended use (surface, binder or base layer), can be considered as “high-performance mixtures”