Probabilistic Viscoelastic Continuum Damage Analysis of Fatigue Life of Warm-Mix Asphalt

Fatigue damage is one of the major distress modes that have a critical impact on the performance and serviceability of asphalt pavements. High variability in testing results poses a challenge for predicting the fatigue life of asphalt mixtures using conventional deterministic modeling approaches. This study examined the efficacy of using a probabilistic approach for the analysis of the viscoelastic continuum damage (VECD) and fatigue life of fine aggregate mixtures (FAM) that were prepared using one hot-mix asphalt (HMA) and three types of warm-mix asphalt (WMA). The FAM mixtures were subjected to oscillating stress-controlled fatigue tests. The results highlighted the differences between the probabilistic and deterministic VECD approaches in representing and predicting fatigue life. In addition, the results demonstrated the advantage of the probabilistic VECD approach in providing more reliable predictions of fatigue life that account for uncertainty in determining the model parameters. The probabilistic analysis results showed that the WMA mixtures tested in this study had less variability but shorter fatigue life than the control HMA mixture.