Effect of key design parameters on high temperature performance of asphalt mixtures

Rutting is one of the main distresses for asphalt pavements and it has adverse effect on service life. It is associated with the high temperature performance of asphalt mixtures. The paper attempts to investigate the effect of key design parameters on high temperature performance of asphalt mixtures. Initially, the factors consisting of air void ratio, compaction effort, maximum nominal particle size and asphalt binder grade were selected and then the uniaxial penetration shear test was applied to analyze the variation of high temperature performance of asphalt mixtures. Accordingly, the maximum penetration load and the shear strength were used as evaluating indicators. Eventually, the multi-way (one way and two-way) ANOVA was adopted to understand the role of factors on the high temperature performance. The results indicate that the high temperature performance increases an average of 30 % when compaction effort and maximum nominal particle size rise. In contrast, the raise of asphalt grade and air void ratio decrease of 10 %similar to 30 % of high temperature performance. At the same time, the increase of compaction effort improves the high temperature performance about 20 %similar to 50 % at two variables condition. In one-way ANOVA, there is no statistically significant difference in the maximum penetration load when changing the air void ratio levels. The compaction effort, maximum nominal particle size, asphalt binder grade significantly influence the change of maximum penetration load. In terms of two-way ANOVA, any combined two factors significantly affect the high temperature results. This provides some guidance for design of asphalt mixtures to elevate high temperature performance.