Laboratory versus plant production: impact of specimen preparation techniques on the performance of balanced mix design asphalt mixtures in Arkansas using the Arkansas choice of performance test

This study evaluated the performance test results of asphalt mixtures from eight BMD field projects approved by the Arkansas Department of Transportation (ARDOT) during 2023 and 2024. The primary objective was to compare performance test results of mixtures fabricated using three sample preparation techniques: laboratory-produced laboratory-compacted (LMLC), plant-produced laboratory-compacted (PMLC), and reheated plant-mix and laboratory-compacted (RPMLC). Initial assessments of rutting and cracking performance were conducted using the Asphalt Pavement Analyzer (APA) and IDEAL-CT, ARDOT's preferred tests. To further validate the findings, five additional tests were performed: tensile strength ratio (TSR), Illinois flexibility index test (I-FIT), Hamburg wheel tracking test (HWTT), dynamic modulus (|E*|) and flow number (FN). The CTIndex results were largely consistent across all sample types, while APA rut depths remained within acceptable ranges without a clear performance trend. TSR, HWTT, I-FIT and FN tests also indicated similar performance test results between LMLC and RPMLC when accounting for variability. RPMLC samples exhibited slightly higher stiffness, as indicated by positive changes in MTSR (19%) and FN (136%), along with negative changes in FI (24%) and HWTT (6%), a trend further supported by the |E*| data. Overall, most mixtures satisfied the BMD performance criteria, demonstrating balanced and reliable asphalt mixture designs.