An optical fibre Bragg grating (FBG) sensor was surface mounted onto a carbon fibre reinforced epoxy composite and subjected to static and dynamic loading. The FBG sensor was found to operate satisfactorily up to 700,000 cycles when the fatigue test was terminated. The fatigue test was conducted at a peak stress of 210 MPa and a stress ratio of -0.5. The FBG sensor was also found to operate satisfactorily over the cyclic loading frequency range of 0.1 - 6 Hz used in this study. The feasibility of using the sensor system for monitoring the stiffness ofthe composite during the fatigue test was demonstrated. The signal processing for the sensor system was based on a CCD spectrometer. The sensitivity of the static strain measurements was found to be approximately 80 jtc. A broadening ofthe FBG reflective spectrum was seen to develop as a function of fatigue cycles, and this phenomenon may be due to the delamination ofthe sensor from the surface ofthe composite.
|Title of host publication||Fiber Optic Sensors V|
|Editors||Kim D. Bennett, Byoung Y. Kim, Yanbiao Liao|
|Number of pages||9|
|Publication status||Published - 24 Sept 1996|
|Event||Fiber optic sensors V - Munich, Germany|
Duration: 22 Jun 1995 → 23 Jun 1995
|Conference||Fiber optic sensors V|
|Period||22/06/95 → 23/06/95|
Bibliographical noteTonguy Liu ; Gerard F. Fernando ; Yun-Jiang Rao ; David A. Jackson ; Lin Zhang and Ian Bennion "In-situ strain measurements in composites during fatigue testing using optical fiber Bragg gratings and a portable CCD detection system", Proc. SPIE 2895, Fiber Optic Sensors V, 249 (September 24, 1996);
Copyright 1996 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.
- smart structures
- optical Fiber sensors
- fibre Bragg grating
- Fatigue damage
- fiber composites