Comparative Study on the Evaluation Methods of the Fracture Resistance of Asphalt Mixtures

Fracture energy based on cohesive zone model,the J-integral based on elastic-plastic fracture mechanics and the failure strain based on elastic failure theory were employed to evaluate the fracture resistance of asphalt mixtures.Effects of asphalt type,asphalt aggregate ratio and temperature on the fracture resistance of the asphalt mixture AC-13F were studied using the three evaluation indicators and sensitivity of the three indicators to the effect factors was also analyzed using the statistical method.The results of the study shows that using the J-integral will over-estimate the contribution of SBS modified asphalt to the fracture resistance of asphalt mixtures,using the failure strain will lead to wrong result for the effect of asphalt aggregate ratio,and all the three indicators are sensitive to the analyzed factors.The fracture energy is recommended to evaluate the fracture resistance of asphalt mixtures by a comprehensive comparison.