Cleaner technologies for asphalt mixtures combining reuse of residual aggregates, waste crumb rubber and warm mix asphalt additive

Abstract

The reuse of waste materials and residual aggregates as well as the reduction of emissions has become vitally important for the environment, the economy and logistics of the asphalt paving industry. This study characterizes the performance and production properties of asphalt mixtures with waste crumb-rubber modifier from scrap tires, a warm mix asphalt surfactant additive and residual poor-quality volcanic aggregates as the single mineral component. The combination of these three cleaner technologies provides a promising solution to produce more sustainable materials by reusing two different types of waste and decreasing the manufacturing temperature at the same time. The compactability, stiffness modulus and fatigue performance characteristics were assessed in the laboratory for different low production temperatures and compared to conventional mixtures. The results indicate that these rubberized warm asphalt mixtures with residual vesicular and scoriaceous aggregates comply with the technical specifications for paving materials. The dynamic properties are maintained or even improved while reusing waste materials and allowing reductions of the manufacturing and compaction temperatures up to 20 °C, therefore, decreasing energy consumption and emissions.