Optimization of the number of design gyrations using the superpave gyratory compactor
This thesis investigates the effect of the laboratory compactive effort on resistance to rutting and cracking of hot-mix asphalt mixtures in Texas. With the objective of improving fatigue resistance of Texas’ asphalt mixtures, two procedures, based on a performance-related approach geared towards determining revised N-design compaction levels to increase binder contents in asphalt mixtures without compromising rutting performance, have been developed: 1) weighted combinations of performance curves, and 2) reliability-based analysis of performance. The experimental design has been devised to investigate the performance characteristics of Texas’ asphalt mixtures designed using the revised N-design. The procedure found strong support for decreasing current N-design levels under most conditions, except for high-volume facilities in warm environments. The number of design gyrations for most condition in Texas could be lowered to 75 to 85 from improved fatigue performance, without significant loss of rutting resistance.