Session: 03-06-01: Damage, Fatigue, and Fracture

Paper Number: 152027

152027 - Implementation of Fatigue Crack Growth Laws in Abaqus 

For many engineering structures, fatigue is the most dominant failure mode. Understanding the fatigue crack growth can be a critical aspect in many structural designs, as it helps limiting and mitigating failure risks due to fatigue loading.

Classically, Paris law had been widely used to model or to predict the fatigue crack growth, however it is incapable of capturing the crack growth nonlinear behavior at the initiation phase thresholds, or near the critical value of the stress intensity factor where the crack propagation is more unstable. Furthermore, Paris Law cannot model the fatigue stress ratio dependency, which is crucial to capture the realistic behavior of structure subject to fatigue stresses under non-symmetric loads. 

Several models in literature, such as Walker, Forman, or NASGRO equations, have addressed the limitations of the Paris law.

In this work, we will present a methodology to implement some of these fatigue crack growth equations into the commercial finite element code Abaqus. This enables the analysis of more realistic engineering structures under realistic cyclic fatigue loading scenarios. Furthermore, we will include the mixed mode behavior to show the influence of difference cracking modes and their interaction on the fatigue behavior and life.

Keywords: NASGRO, Fatigue crack growth, Fracture Mechanics, Mixed Mode behavior, Finite Element Analysis.

Presenting Author: Hicham Farid Dassault Systèmes

Presenting Author Biography: Dr. Hicham Farid has a PhD in Mechanical Engineering from the University of Quebec, Canada, where his research focused on Fracture Mechanics. His primary research interests are material modeling and calibration, fracture mechanics, fatigue and creep. Prior to joining Dassault Systèmes, Dr. Farid spent 12 years working as R&D Engineer/Scientist at leading organizations in the aerospace, nuclear, and renewable energy industries.