An anisotropic, brittle damage model for finite strains with a generic damage tensor regularization

TL;DR

This paper introduces a universal anisotropic damage model framework for finite strains that ensures mesh-independent results through micromorphic gradient-extensions, demonstrated with Neo-Hookean materials and applied to structural and rotor blade simulations.

Contribution

It develops a flexible, mesh-independent damage modeling framework for finite strains that integrates various hyperelastic formulations using micromorphic gradient-extensions.

Findings

The model satisfies damage growth criteria for Neo-Hookean materials.

Volumetric-deviatoric regularization is identified as efficient.

Successful simulation of a pressure-loaded rotor blade demonstrates the framework's applicability.

Abstract

This paper establishes a universal framework for the nonlocal modeling of anisotropic damage at finite strains. By the combination of two recent works, the new framework allows for the flexible incorporation of different established hyperelastic finite strain material formulations into anisotropic damage whilst ensuring mesh-independent results by employing a generic set of micromorphic gradient-extensions. First, the anisotropic damage model, generally satisfying the damage growth criterion, is investigated for the specific choice of a Neo-Hookean material on a single element. Next, the model is applied with different gradient-extensions in structural simulations of an asymmetrically notched specimen to identify an efficient choice in the form of a volumetric-deviatoric regularization. Thereafter, the universal framework, which is without loss of generality here specified for a Neo-Hookean material with a volumetric-deviatoric gradient-extension, successfully serves for the complex simulation of a pressure loaded rotor blade. After acceptance of the manuscript, we make the codes of the material subroutines accessible to the public at https://doi.org/10.5281/zenodo.11171630.