Burst Tests with Acoustic Emission Monitoring of Filament Wound GFRP Pipes

Glass Fibre Reinforced Plastic (GFRP) pipes, (90/0/90°)n and (0/55°)n (n = 1-3) in lay up, were subjected to hydrostatic tests in a Hammel Sciteq P400 machine, by which an internal pressure was applied through water inlet. During mechanical characterisation tests, carried out at the aim to compare the performances of the different stacking sequence, the specimens were continuously monitored by two Acoustic Emission (AE) sensors. The scope of AE analysis was twofold: a) to verify the usefulness of typical AE parameters in identifying the different failure modes occurring during loading; b) to attempt an effective localisation of the damage, rendered difficult by the acoustic anisotropy of the material. Good results were obtained by the theoretical formulation about the prediction of the behaviour of the different stacking sequence, in a good agreement with the AE system revealing a good solution for the on line monitoring of the pipes performances.