Open AccessImproved Probabilistic Modeling of Multi-Site Fatigue Cracking
Author(s) -
Abdallah Al Tamimi,
Mohammad Modarres
Publication year - 2020
Publication title -
international journal of prognostics and health management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.336
H-Index - 21
ISSN - 2153-2648
DOI - 10.36001/ijphm.2015.v6i4.2288
Subject(s) - coalescence (physics) , paris' law , probabilistic logic , structural engineering , materials science , cracking , stress intensity factor , fatigue cracking , intensity (physics) , stress concentration , fracture mechanics , computer science , composite material , crack closure , engineering , physics , quantum mechanics , artificial intelligence , astrobiology
The purpose of this paper is to investigate the effect of fatigue, in the presence of neighboring cracks, and to integrate that into a model that could be used to predict crack growth. A total of 20 fatigue experiments were performed at different loading conditions using dog-bone samples of API-5L grade B carbon steel containing neighboring cracks. The impact of the neighboring cracks dimensions and the loading conditions on the interaction, coalescence and growth of cracks were investigated. A design of experiment approach to study neighboring cracks interactions and growth in carbon steel materials is also presented. Simulation efforts were performed to assess the Stress Intensity Factor (SIF) around neighboring cracks. Models discussing how the SIF of single semi-elliptical crack could be corrected to account for the neighboring cracks interaction were discussed in order to better understand the fatigue behavior. A combination of these models was integrated to find the SIF values necessary for the probabilistic life prediction modeling purposes. Finally, a multi-site fatigue crack growth rate model was developed and its parameters including their uncertainties were estimated. A Bayesian approach was adopted to perform uncertainty characterization and model validation.