Three-Dimensional Fem-Dem Coupling Simulation for Analysis of Asphalt Mixture Responses Under Rolling Tire Loads

As traffic grows by leaps and bounds, deterioration of asphalt surface layers emerges as the primary cause of road network costs. A deep understanding of the tire-pavement interaction is essential for optimizing the surface design of asphalt pavements in the context of aging infrastructure and limited maintenance resources. Most of the current tire-pavement interaction studies have been conducted in the continuum mechanics framework using Finite Element Methods (FEM), which shows limitations in modeling the discontinuity nature of asphalt mixtures. Discrete Element Methods (DEM) offer a promising way to examine the mechanical properties of asphalt mixtures at the particle level, but it is inadequate for modeling deformable tire structure and capturing realistic tire contact forces on the pavement surface. In this study, a FEM-DEM coupling strategy was developed for the modeling of tire-pavement interaction by implementing a DEM model of asphalt mixtures with rolling tire loads from a FEM model. Based on simulations with realistic rolling tire load conditions, this coupling algorithm allows the investigation of particle force chain network evolution, particle displacement and velocity distributions, movements of individual particles, and particle contact force characteristics inside an asphalt mixture. This study offers an enriching expansion of both continuum and discrete mechanics methods for analyzing asphalt mixture responses under rolling tire loads, which can provide insight into pavement surface design.