Compactability and performance of superpave mixtures with aggregate structures designed using the Bailey method

This study analyzes the compaction and performance characteristics of asphalt concrete mixtures with aggregate structures that were designed using the Bailey method of aggregate gradation evaluation. Three aggregate types were considered in this study: limestone, sandstone, and granite. All the aggregates were crushed. Three different aggregate structures were designed for each aggregate type. All the mixtures had a nominal maximum aggregate size (NMAS) of 12.5mm, and were designed for high traffic level. During compaction, force measurement was made using a small accessory inserted in the compaction mold called the Pressure Distribution Analyzer (PDA). The compaction characteristics of the mixtures were analyzed using data from the PDA and the traditional Superpave Gyratory Compactor (SGC) data. Simulative (Hamburg Wheel Tracking Test) and fundamental (Indirect Tensile Strength Test, and Semi-Circular Fracture Test) tests were conducted to determine laboratory performance properties and evaluate the mixtures under different loading and environmental conditions. The compaction characteristics and gradation parameters were correlated with the results from the laboratory tests. The data indicate that the designed mixtures considered were impermeable and presented excellent resistance to rutting and moisture damage.