English

A convergent adaptive finite element method for a phase-field model of dynamic fracture

Numerical Analysis 2025-10-08 v1 Numerical Analysis

Abstract

We propose and analyze an adaptive finite element method for a phase-field model of dynamic brittle fracture. The model couples a second-order hyperbolic equation for elastodynamics with the Ambrosio-Tortorelli regularization of the Francfort-Marigo variational fracture energy, which circumvents the need for explicit crack tracking. Our numerical scheme combines a staggered time-stepping algorithm with a variational inequality formulation to strictly enforce the irreversibility of damage. The mesh adaptation is driven by a residual-based a posteriori-type estimator, enabling efficient resolution of the evolving fracture process zone. The main theoretical contribution is a rigorous convergence analysis, where we prove that the sequence of discrete solutions generated by the AFEM converges (up to a tolerance) to a critical point of the governing energy functional. Numerical experiments for a two-dimensional domain containing an edge-crack under dynamic anti-plane shear loading demonstrate our method's capability of autonomously capturing complex phenomena, including crack branching and tortuosity, with significant computational savings over uniform refinement.

Keywords

Cite

@article{arxiv.2510.05407,
  title  = {A convergent adaptive finite element method for a phase-field model of dynamic fracture},
  author = {Ram Manohar and S. M. Mallikarjuaniah},
  journal= {arXiv preprint arXiv:2510.05407},
  year   = {2025}
}