Inner strain determination of three-dimensional braided preforms with co-braided optical fiber sensors

Abstract

The experimental characterization of three-dimensional (3-D) braided composites is extremely important for their design and analysis. Because of their desirable attributes and outstanding performance, optical fiber sensors (OFSs) can be embedded to monitor mechanical properties of textile composites. This paper discusses two techniques to incorporate different OFSs into 3-D braided composite preforms. The operating principle of various sensor systems is first conducted. Experiments using Michelson interferometers, FBG sensors, and micro-bend sensors are performed to verify the concept of the proposed method. Strain curves of various OFSs tests are finally compared, and they all exhibit good linearity.

References

1. Kamiya R, Cheeseman B A, Proper P, Chou T W . Some recentadvances in the fabrication and design of three-dimensional textilepreforms: a review. Composite Science andTechnology, 2000, 60(1): 33–47. doi:10.1016/S0266-3538(99)00093-7
2. Sun X K, Sun C J . Mechanical properties of3-D braided composites. Composite Structure, 2004, 65(4): 485–492. doi:10.1016/j.compstruct.2003.12.009
3. Udd E . FiberOptic Smart Structures. New York: Wiley, 1995
4. Li X H, Zhao C S, Lin J, Yuan S F . The internalstrain of three-dimensional braided composites with co-braided FBGsensors. Optics & Lasers in Engineering, 2007, 45(7): 819–826. doi:10.1016/j.optlaseng.2006.12.003
5. Yuan L B, Zhou L M, Jin W, Lau K T, Poon C K . Effect of thermally induced strain onoptical fiber sensors embedded in cement-based composites. Optical Fiber Technology, 2003, 9(2): 95–106. doi:10.1016/S1068-5200(03)00005-1
6. Yuan S F, Ansari F, Liu X, Zhao Y . Optic fiber-baseddynamic pressure sensor for WIM system. Sensors and Actuators A-Physical, 2005, 120(1): 53–58. doi:10.1016/j.sna.2004.11.008
7. Tao X M, Tang L Q, Du W C, Choy C L . Internalstrain measurement by fiber Bragg grating sensors in textile composites. Composite Science and Technology, 2000, 60(5): 657–669. doi:10.1016/S0266-3538(99)00163-3
8. Botsis J, Humbert L, Colpo F, Giaccari P . Embeddedfiber Bragg grating sensor for internal strain measurements in polymericmaterials. Optics & Lasers in Engineering, 2005, 43(4): 491–510. doi:10.1016/j.optlaseng.2004.04.009
9. Kuang K S C, Kenny R, Whelan M P, Cantwell W J, Chalker P R . Embedded fibre Bragg gratingsensors in advanced composite materials. Composite Science and Technology, 2001, 61(10): 1379–1387. doi:10.1016/S0266-3538(01)00037-9
10. Gauthier R C, Ross C . Theoretical and experimentalconsiderations for a single-mode fiber-optic bend-type sensors. Applied Optics, 1997, 36: 6264–6273. doi:10.1364/AO.36.006264