A thermomechanical framework for modeling the compaction of asphalt mixes

Compaction of asphalt mixes is a very important process that is known to influence the performance of these mixes. This study is aimed at developing a nonlinear model for the compaction process within a thermodynamic framework that exploits the notion of a body possessing multiple natural configurations. By specifying the forms for the stored energy, the rate of dissipation, the heat flux vector, etc., for the material, a specific model is developed to describe and study asphalt mix compaction. The phenomenon of compaction requires the development of a compressible viscoelastic material to describe the response of asphalt mixes. A numerical scheme was developed to solve the equations governing compaction and the results were compared with results from experiments that were carried out. The agreement with the experimental results are quite good indicating that this model may be used to predict the compactability of asphalt mixes and in the design of asphalt mixes that can be compacted in the field to achieve desirable performance characteristics.