Modal analysis of acoustic emission signals from CFRP laminates

As a result of its continuous and in situ detection capabilities, the acoustic emission (AE) technique is the prime candidate for damage monitoring in loaded composite structures. None of the AE analysis techniques used in laboratory studies has, however, proven to be capable of consistently dealing with the difficulties encountered in larger structures: large amount of data, the elimination of noise sources and the influence of wave propagation effects (attenuation, dispersion). This work will use the modal acoustic emission (MAE) technique as a more intelligent and efficient way of analysing AE results. AE waveforms obtained during tensile and bending testing of CFRP laminates will be presented. It will be demonstrated how taking into account the modal nature of AE waves can in future lead to more quantitative and accurate results. (C) 1999 Elsevier Science Ltd. All rights reserved.