Development of an index to evaluate the cracking potential of asphalt mixtures using the semi-circular bending test

This study introduced a cracking parameter, called the Cracking Resistance Index (CRI), derived from the load-displacement response obtained during a semi-circular bending test, and compared it to the recently developed Flexibility Index (FI). Laboratory test results indicated that both FI and CRI are sensitive to binder Performance Grade, recycled materials content, and recycling agent dosage. The results indicated the dependency of the two indices on specimen thickness and air voids content. A reasonable correlation between FI and CRI was verified. As compared to the FI, the proposed CRI provided better distinction between different asphalt mixtures, less variability, and easier calculation.