# A simulation method for fatigue-driven delamination in layered structures involving non-negligible fracture process zones and arbitrarily shaped crack fronts

## TL;DR

This paper introduces a new 3D cohesive zone-based computational method for simulating fatigue-driven delamination in layered structures, accurately predicting crack growth without fitting parameters and validated against experimental data.

## Contribution

The paper presents a novel 3D simulation method that accounts for non-negligible fracture process zones and arbitrarily shaped crack fronts, validated with experimental benchmarks.

## Key findings

- Accurately predicts fatigue delamination in 3D structures.
- Does not require fitting parameters, using experimental inputs.
- Validated against experimental benchmark cases.

## Abstract

Most of the existing methods for fatigue-driven delamination are limited to two-dimensional (2D) applications or their predictive capabilities have not been validated in three-dimensional (3D) problems. This work presents a new cohesive zone-based computational method for simulating fatigue-driven delamination in the analysis of 3D structures without crack migration. The method accurately predicts fatigue propagation of non-nelgigible fracture process zones with arbitrarily shaped delamination fronts. The model does not require any kind of fitting parameter since all the input parameters are obtained experimentally from coupon tests. The evaluation of the energy release rate is done using two new techniques recently developed by the authors (the growth driving direction and the mode-decomposed J-integral) leading to an accurate prediction of delamination propagation under mixed-mode and non-self-similar growing conditions. The new method has been implemented as a UEL for Abaqus and validated against an experimental benchmark case with varying crack growth rate and shape and extension of the fracture process zone.