Aggregate Toughness/Abrasion Resistance and Durability/Soundness Tests Related to Asphalt Concrete Performance in Pavements

TLDR

Numerous aggregate tests exist, yet many lack strong links to final pavement performance, especially for toughness, abrasion resistance, durability, and soundness. The study aimed to identify and evaluate toughness/abrasion resistance and durability/soundness tests for aggregate used in asphalt concrete, selecting those that best predict field performance. By reviewing literature and specifications, the authors chose a suite of laboratory tests, evaluated 16 aggregate sources with varied performance histories, collected pavement performance data from state agencies, and correlated lab results with field outcomes. Micro‑deval and magnesium sulfate soundness tests exhibited the strongest correlation with asphalt concrete field performance and are recommended for aggregate characterization.

Abstract

Numerous tests have been developed that empirically characterize aggregate without, necessarily, having a strong relationship to the performance of the final products incorporating these aggregates. This seems to be particularly true for aggregate toughness and abrasion resistance and durability and soundness. Toughness/abrasion resistance and durability/soundness tests for characterizing aggregate used in asphalt concrete were identified and evaluated, and those test methods that best correlate with field performance were determined. Based on a review of literature and specifications, laboratory tests for characterizing aggregate toughness/abrasion resistance and durability/soundness were selected. Sixteen aggregate sources with poor to good performance histories were identified for evaluation with the selected suite of tests. Performance histories of pavements containing these aggregates in asphalt concrete layers were established through personal contacts with state transportation agencies and performance evaluation questionnaires. Aggregate properties from laboratory tests were correlated with field performance. The micro-deval and magnesium sulfate soundness tests provide the best correlations with field performance of asphalt concrete and are recommended for characterizing aggregate toughness/abrasion resistance and durability/soundness.