Determining appropriate level of detail of 3D aggregate model for accurate and efficient mesoscopic simulation of asphalt concrete

The levels of detail (LODs) of aggregate models significantly impact both the accuracy and efficiency of the mesoscale numerical simulation of asphalt concrete. This study proposed a quantitative evaluation framework to find an appropriate LOD that allows accurate simulation of asphalt concrete with relatively low model complexity. First, the coarse aggregates in asphalt concrete were reconstructed from computed tomography (CT) images, and their LOD was defined as level-0. Each reconstructed aggregate was then simplified using a surface simplification method that obtains aggregate models with four descending LODs (levels-1, 2, 3 and 4), consisting of 200, 100, 50 and 20 triangular facets respectively. The simulation accuracy was evaluated according to several aggregate geometric indexes and mesoscopic finite element (FE) compressive simulation results of asphalt concrete. The results indicate that compared to the level-1 model, the level-2 model can achieve a similar simulation accuracy with a 50% reduction in simulation time.