Mixed mode I+II fracture parameters and cracking trajectory of heterogeneous multilayer pavement structure containing reflective crack

Using aggregate generation and packing algorithm technique coupled with finite element method, a part of reconstructed asphalt pavement structure with five layers and containing a bottom‐up crack was simulated. For more realistic modeling and more accurate analyzing the cracking behavior of pavement, a region surrounding the initial crack (and bottom‐up crack) region and its neighborhood was modeled as a heterogeneous two‐phase (aggregate/mastic) mixture. The results of numerical analyses showed that a significant difference exists between the crack tip fracture parameters (i.e., KI, KII, Keff, T‐stress, and Biaxiality ratio) of the homogenous and heterogeneous models. The heterogeneous simulation (in this case study) leads to approximately 70% reduction in the effective stress intensity factor. Furthermore, it was shown that the fracture trajectory of a simulative reflective cracking (SRC) test conducted on a real bilayer asphalt beam sample can be predicted well by modeling the beam layers as a heterogeneous two‐phase mixture.