Delamination detection and characterisation of bridging tractions using long FBG optical sensors

Measurements of non-uniform strains due to the propagation of mode-I delamination and identification of bridging tractions in double cantilever beam (DCB) composite specimens made of uniaxially reinforced AS4/PPS are presented. A fibre Bragg grating (FBG) of 22 or 35 mm is embedded parallel to the reinforcing fibres, during consolidation and above the delamination plane. Strain distributions along the sensor are obtained by optical low-coherence...