A comparison of micro-mechanical modeling of asphalt materials using finite elements and doublet mechanics

A comparative study is given between two micro-mechanical models that have been developed to simulate the behavior of cemented particulate materials. The first model is a discrete analytical approach called doublet mechanics that represents a solid as an array of particles. This scheme develops analytical expressions for the micro-deformation and stress fields between particle pairs (a doublet). The second approach is a numerical finite element method that establishes a network of elements between neighboring cemented particles. Each element has been developed to model the local load transfer between particles. While the two modeling schemes come from very different beginnings, they have a fundamental similarity. However, they also have some basic differences. In order to pursue these similarities and differences, three example problems are investigated using each modeling approach. Even with the differences, the two model predictions of the micro-stress distributions for each example compared quite closely. These results also indicated significant micro-structural effects that differ from continuum elasticity theory and could lead to better explanations of observed failures of these types of materials.