Journal of the Korean Society for Nondestructive Testing (비파괴검사학회지)

The Korean Society for Nondestructive Testing (한국비파괴검사학회)
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Strain Transmission Characteristics of Packaged Fiber Bragg Grating Sensors for Structural Health Monitoring

  • Cho, Sung-In (Division of Aerospace Engineering, KAIST) ;
  • Yoo, Seung-Jae (Division of Aerospace Engineering, KAIST) ;
  • Kim, Eun-Ho (Division of Aerospace Engineering, KAIST) ;
  • Lee, In (Division of Aerospace Engineering, KAIST) ;
  • Kwon, Il-Bum (Center for Safety Measurement, Korea Research Institute of Standards and Science) ;
  • Yoon, Dong-Jin (Center for Safety Measurement, Korea Research Institute of Standards and Science)
  • Received : 2010.03.25
  • Accepted : 2010.06.10
  • Published : 2010.06.30
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Abstract

Fiber Bragg grating(FBG) sensor arrays can be used to monitor the mechanical behavior of the large composite structures such as wind turbine rotor blades and aircrafts. However, brittle FBG sensors, especially multiplexed FBG sensors are easily damaged when they are installed in the flexible structures. As a protection of brittle FBG sensors, epoxy packaged FBG sensors have been presented in this paper. Finite element analysis and experiments were performed to evaluate the effects of adhesives, packaging materials and the bonding layer thickness on the strain transmission. Two types of epoxy were used for packaging FBG sensors and the sensor probes were attached with various bonding layer thickness. It was observed that thin bonding layer with high elastic modulus ratio of the adhesive to packaging provided good strain transmission. However, the strain transmission was significantly decreased when elastic modulus of the adhesive was much lower than the packaged FBG sensor probe's one.

Keywords

References

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