Application study on FBG sensor applied to hull structural health monitoring

Ships sail in complicated marine environment, affected by winds, waves, impact and other loads. On the base of hull structure stress and strain monitoring, this paper put forward two types of fiber Bragg grating (FBG) strain rosettes to measure the complex stress and strain of hull plane. Several main factors affecting the strain transfer ratio were analyzed to optimize the type and size of strain rosettes through the finite element analysis. Finally, experimental research on the optimizing FBG strain sensor was conducted through the tensile machine, and compared with the results of electric resistance strain. It is concluded that the designed strain rosette structure has a good sensitivity, resilience, and long-term stability, which is fully applicable to hull structure health monitoring under the environment of corrosion and fatigue loading.