A phase field model for damage in asphalt concrete

ABSTRACT

In this work, a phase field approach to modelling fracture in asphalt mixtures is presented. More specifically, a cohesive zone-based phase field model is used. The crack in the material is modelled as a regularised damage, smeared over a region of finite length, using a damage phase field variable. The damage variable takes on the value of 1 for a fully damaged surface to 0 for an intact solid. The energy dissipated due to inelastic behaviour in the damage zone is modelled using a cohesive zone concept and the associated traction-separation constitutive law. The model is implemented in a finite element framework. Several numerical examples are presented to show the performance of the model in simulating fracture in asphalt mixtures at low temperatures. Fracture under mode-I, mode-II and mixed mode is simulated. The numerical results of crack initiation and propagation agrees well with experimental observations.

KEYWORDS:

• Phase field model
• cohesive zone
• asphalt mixture
• mixed-mode cracking

Acknowledgments

The authors would like to thank Dr. Erik Jan Lingen, Software Director at the Dynaflow Research Group, Zoetermeer, the Netherlands for providing help and support on the numerical toolkit JEM/JIVE.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 JIVE is an open source C++ numerical toolkit for solving partial differential equations and building numerical applications, https://software.dynaflow.com/jive