Theory Analysis of FBG Characteristics under 3D homogeneous stress field

摘要

FBG sensing characteristics and model under three-dimensional stress are studyed in this paper. Theory analysis indicates that the reflection spectra of FBG is gradually splitted into two resonance peaks with the increase of the load and the two resonance peaks have a linear relation to the load. The difference of the wavelength sensitivity of the two directions of FBG is much less than the conditions of FBG only under transverse force, that is to say, the axial force plays a leading role in the shift amount of center wavelength.