TY  - EJOU
AU  - Minakuchi, Shu  
AU  - Mizutani, Tadahito  
AU  - Tsukamoto, Haruka  
AU  - Nishio, Mayuko 
AU  - Okabe, Yoji  
AU  - Takeda, Nobuo  

TI  - Brillouin Spectral Response Depending on Strain Non-Uniformity within Centimeter Spatial Resolution and its Application to Internal Damage Detection in Large-Scale Composite Structures
T2  - Structural Durability \& Health Monitoring

PY  - 2008
VL  - 4
IS  - 4
SN  - 1930-2991

AB  - The authors propose a technique to detect centimeter internal damages in large-scale composite structures, using an optical fiber network running throughout the structure. A Brillouin-based distributed strain sensing system with centimeter-order spatial resolution (pre-pump pulse Brillouin optical time domain analysis (PPP-BOTDA)) was utilized to detect residual non-uniform strain in the damaged area. First, Brillouin spectral response depending on the strain profile within the spatial resolution was revealed. The spectral response depending on strain non-uniformity was experimentally quantified with consideration of the general characteristics of the Brillouin gain spectrum. Then, the damage detection procedure was proposed, based on the spectral response. Finally, impact damage detection of a composite sandwich structure was numerically conducted to illustrate the effectiveness of the proposed technique. The developed system is quite useful in a first inspection of large-scale composite structures in aerospace applications.
KW  - 

DO  - 10.3970/sdhm.2008.004.199