Abstract
In this paper, we propose a novel approach to characterise barely visible transverse matrix cracks in composite structures using fibre Bragg grating (FBG) optical sensors. Matrix cracks are one of the most prevalent types of damage in composite structures, and detecting them in the internal layers of composites has remained a challenge. In this paper, we will show that the formation of cracks in the internal layers of composite structures alters the side-lobes of the reflection spectra of FBG sensors by adding new harmonics to them. We argue that the spread and the location of these harmonics depends on both the mechanical properties of the composite material and the location of the crack along the length of the FBG sensor. Via computer simulations and experimental measurements, we validate our hypotheses, and the results are in agreement with our model.
| Original language | English |
|---|---|
| Article number | 8723555 |
| Pages (from-to) | 4720-4727 |
| Number of pages | 8 |
| Journal | Journal of Lightwave Technology |
| Volume | 37 |
| Issue number | 18 |
| DOIs | |
| Publication status | Published - 2019 |
Bibliographical note
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-careOtherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Keywords
- Barely visible damage
- Composites
- FBG
- Fiber Bragg gratings
- Matrix cracks
- Reflection spectrum
- Smart structures
- Structural health monitoring (SHM)