Using notched semi circular bending fatigue test to characterize fracture resistance of asphalt mixtures

• A new fracture mechanics approach proposed using SCB fatigue test.
• The new approached was realized in the study.
• The approached was verified through FEM analysis and experiment.

This paper presents a new method of using the notched semi circular bending (SCB) fatigue test to characterize the fracture resistance of asphalt mixtures. In order to achieve this goal, finite element analysis (FEA) was first performed to establish the correlations of effective crack length vs. deformation and stress intensity factor vs. effective crack length. Notched SCB fatigue test was then conducted on four asphalt mixtures made with different asphalt binders. Using the correlations developed by FEA and following the suggested procedures, the curves of deformation vs. loading cycles from the fatigue test were converted to fit the Paris law. The fracture parameters were finally obtained by regression analysis. The results show that the fracture parameters from this study agreed well with those found in the published literature, indicating that the proposed method was valid for characterizing the fracture resistance of asphalt mixtures. The results also show that the change in asphalt binder properties caused by adding different additives eventually resulted in the differences in fracture resistance of asphalt mixtures.