Influence of Mixture Properties on Fracture Mechanics in Asphalt Mixtures

This paper reports a research study aimed at providing insight into key mechanisms and mixture properties that influence fracture in asphalt concrete. The experimental analysis was based on the Hot Mix Asphalt (HMA) Fracture Mechanics visco-elastic crack growth law. HMA cracking mechanism was investigated using multiple laboratory test configurations on both unmodified and polymer modified mixtures. A Digital Image Correlation (DIC) was employed to more accurately capture localized or non-uniform stress distributions in asphalt mixtures and as a tool for detecting first fracture. Crack initiation and crack growth were predicted effectively using a Displacement Discontinuity (DD) boundary element method.