Mechanical And Acoustic-Emission Response Of Unidirectional And Cross-Plied Grp Laminates

This paper deals with characterisation of damage accumulation in unidirectional and cross-ply (0,90) 2s and (90,0) 2s glass fibre reinforced plastics (GRP) subjected to monotonic uniaxial tensile tests. Damage accumulation and in-plane mechanical behaviour are both continously monitored by acoustic emission (AE) and triaxial strain gauge techniques. The purpose of the study is to correlate specific features of the acoustic and mechanical responses and to characterise the onset of damage mechanisms. The changes of the local compliances and the simultaneous appearance of high amplitude events and high emission rates are induced by transverse cracking and clearly depend on the stacking sequence. The importance of an AE distribution with a logarithmic scale is emphasised.