Evaluation of Aggregate Crushing Tests and Their Correlation with Superpave Mix Design Properties

Abstract

This paper evaluated alternative test methods to determine the crushing potential of aggregates and documented the influence of aggregate characteristics on the engineering properties of asphalt mixes. Six aggregates sampled from different sources were subjected to various aggregate tests, including the Los Angeles abrasion, micro-Deval, soundness magnesium, and acid insoluble tests. A Superpave mix with a 12.5-mm (1/2-in.) nominal maximum aggregate size gradation was produced with each aggregate source using the same PG 64-22 asphalt binder. The mixtures were produced to investigate the impact of aggregate properties on their volumetric properties as well as the tensile strength from the indirect tension tests and rutting potential from the Hamburg wheel tracking tests. Correlation analyses among the measured parameters identified the aggregate crushing value as a promising alternative test method to quantify the crushing potential of aggregates and to adjust the gradation accordingly to produce mixtures with optimized volumetric properties.