Evaluation of the low temperature cracking performance of asphalt mixtures utilizing HMA fracture mechanics

In the present study, the low temperature cracking performance of asphalt mixture has been investigated numerically and experimentally. To do so, the HMA thermal fracture model has extended by including fracture energy threshold and non-linear thermal contraction coefficient. This extended model is capable to predict thermally induced stress and fracture temperature, which is validated with experimental results obtained from three different types of asphalt mixtures. From the parametric study, it was observed that understanding the influence of thermal contraction coefficient, the cooling rate and the creep compliance parameters can make a significant contribution to the material's sustainability. From the analysis, it was found that this extended model can be utilized to evaluate the low temperature cracking performance of asphalt mixtures and capable to provide correct ranking. Interestingly, non-linear thermal contraction coefficient gave much better prediction than linear approach.