Development of Gyratory Stability Index to Evaluate Variation of RAP Content and Rutting Resistance of Asphalt Mixtures

UI-19-03ITD Research Report RP 175 developed an algorithm for determining a Gyratory Stability (GS) for asphalt mixtures based on the Servopac gyratory compactor. The GS describes the ability of asphalt mixtures to resist rutting, and it can be determined during the mix design stage using the gyratory compaction data. This study developed a modified algorithm for GS applicable to Pine Gyratory compactor model AFG2AS which is used by ITD districts. In addition, this study investigated the use of the GS, other gyratory compaction indices, and performance tests to detect the variations in mix composition. The researchers prepared and tested laboratory-mixed laboratory-compacted (LMLC) mixes and plant-mixed laboratory-compacted (PMLC) mixes obtained from new paving projects