A Residual Thermal Stress Calculation of Asphalt Based on a Coupled Viscoelastic Phase-Field and Navier-Stokes System
Yue Hou, Linbing Wang, Wenjuan Sun · 2014
The residual thermal stress in asphalt due to temperature fluctuations greatly affects pavement stability and service life of pavement structures. In this paper, a coupled viscoelastic phase-field and Navier-Stokes system for the residual thermal stress in asphalt binder is developed. We simplify the asphalt binder to two compositions, resin and oil. The phase separation is modeled by the conserved Cahn-Hilliard dynamics, which is coupled with the fluid module in COMSOL commercial software. In order to capture the deforming interface, a self-adaptive mesh is employed for the finite element calculations. The numerical results show that the phase separation phenomenon has a significant influence on the residual thermal stress and leads to a non-uniform stress distribution in the system. Furthermore, stress concentration is observed at microstructure boundaries.