Abstract
In 2009 the FAA introduced a slow-growth approach for certifying composite and adhesively-bonded structures. In the case of adhesively-bonded repairs this approach requires that the growth of any disbond is slow, stable and predictable under cyclic-fatigue loads. The present paper addresses the challenge of developing a methodology, based upon fracture-mechanics, which is capable of enabling this approach to be implemented. We have examined the growth of disbonds from small naturally-occurring material discontinuities in adhesively-bonded structures which are typical of aerospace bonded-repairs. It is shown that the disbond growth histories can be accurately modelled using a form of the Hartman and Schijve equation to describe the measured fatigue properties of the adhesive, coupled with a finite-element analysis of the bonded repair. It is also shown that the scatter in the disbond growth histories can be captured by allowing for small changes in the fracture-mechanics threshold term. These findings suggest that the Hartman-Schijve crack-growth equation has the potential to address the 'slow growth' approach to certifying adhesively-bonded structures and bonded repairs outlined in the US FAA Airworthiness Advisory Circular No: 20-107B.
Original language | English |
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Title of host publication | ICF 2017 - 14th International Congress on Fracture |
Editors | Emmanuel E. Gdoutos |
Publisher | International Conference on Fracture |
Pages | 31-32 |
Number of pages | 2 |
ISBN (Electronic) | 9780000000002 |
Publication status | Published - 2017 |
Event | International Congress on Fracture 2017 - Rhodes, Greece Duration: 18 Jun 2017 → 20 Jun 2017 Conference number: 14th https://www.icfweb.org/icf/ (Website) |
Conference
Conference | International Congress on Fracture 2017 |
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Abbreviated title | ICF 2017 |
Country/Territory | Greece |
City | Rhodes |
Period | 18/06/17 → 20/06/17 |
Internet address |
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Keywords
- Bonded repairs
- Fatigue
- Hartman and Schijve
- Life prediction
- Modelling fatigue