Failure characterisation of sandwich beams using integrated acoustic emission and digital image correlation techniques

The paper presents the experimental study of the failure behaviour of sandwich beams subjected to bending. The samples examined are sandwich beams made of polyethylene terephthalate foam core and glass fibre-reinforced polymer laminate face sheets. In a series of experiments, it has been proposed to integrate diagnostic techniques with acoustic emission and digital image correlation to accurately track the cracking process on the surface as well as in the entire volume of the beam. The research programme carried out allowed observing various modes of failure in composite specimens. The results obtained showed that the integration of acoustic and optical diagnostic techniques provided complementary results and can be used successfully for failure monitoring in sandwich beams.