Investigation of the fatigue properties of asphalt mixture designed using vertical vibration method

Abstract

In this work, the flexural tensile fatigue behaviours of AC-20 asphalt mixtures were studied using beams, which were designed by the vertical vibration method (VVTM) and Marshall method. Then an analysis of variance (ANOVA) was used to examine the differences in fatigue lives, and the Weibull distribution was used to analyze the fatigue lives and establish the fatigue equations of the mixtures. Subsequently, the fatigue lives were compared and analyzed under the same stress level and repeated load force. The results showed that the test accuracy of specimens produced using the vertical vibration compaction method (VVCM) exceeds 92%. Compared to the Marshall design, the asphalt mixture fabricated with the VVTM design improved crack resistance and rutting resistance by at least 40% and 30%, respectively. The ratio of the slopes (the values of the regression coefficient b) of fatigue equations of asphalt mixtures designed by the VVTM to that of Marshall method ranges from 0.883 to 0.965, and the ratio of the intercepts (the values of the regression coefficient a) ranges from 1.278 to 1.284. The results also showed that compared to the Marshall design, asphalt mixtures fabricated with VVTM design exhibited improved fatigue lives by at least 61% (at a stress level of 0.45) and 356% (with a repeated load force of 0.378 kN).