Porous Asphalt Mixture with a Combination of Solid Waste Aggregates

Abstract

The strategy of blending a low-utility waste stream (glass) into a well-recyclable stream [recycled concrete aggregate (RCA)] was applied that entailed evaluating porous asphalt mixture (PAM) made of RCA and glass. Two hybrid PAM designs containing 78% RCA, together with 16% glass particles as smallest-sized or as medium-sized aggregate component, were evaluated against two control groups comprising full-granite and full-RCA aggregates, respectively. An experiment designed to assess the bonding effect between asphalt and aggregates showed that glass particles possessed the weakest bonding effect with asphalt as compared with granite and RCA. Optimal asphalt content (OAC) was determined based on Cantabro test, draindown test, and Marshall test. For the two hybrid PAMs, mixture containing fine glass was more resistant against abrasion but weaker in dynamic creep test than the mixture containing medium-sized glass. On the whole, PAM material made with waste materials can meet the relevant requirements in performance tests and are considered suitable for direct applications in low-strength pavements such as pedestrian and cyclist pathways.