Modeling of Asphalt Concrete Fracture Tests with the Discrete-Element Method

Abstract

In this work, the discrete-element method was used to simulate crack propagation in asphalt concrete in two types of laboratory tests: the disk-shaped compact (DCT) test and the single-edge-notched beam (SEB) test with the three-point bending technique. The heterogeneous models were numerically simulated using the clump technique to represent the shapes of the aggregate, the particle size distribution, and the air voids in the asphalt concrete mixture. The overall mechanical behavior and the fracture propagation were simulated by the cohesive zone model, in the potential fracture area, and the viscoelastic Burger’s model, in the remaining region of the samples. To obtain the values of the micro parameters required for the discrete-element model, a trial and error process was carried out comparing the mechanical behavior observed when considering the macro parameters of the asphalt concrete determined in laboratory tests. The numerical and experimental results are in good general agreement.