PSI - Issue 54

Claudia Barile et al. / Procedia Structural Integrity 54 (2024) 225–232 C. Barile et al. / Structural Integrity Procedia 00 (2023) 000–000

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The AE signals in Cluster 4 begin to appear abundantly just before the failure: 5000 µϵ in Specimen 1, which failed at 5125 µϵ ; 4300 µϵ in Specimen 2 and 6000 µϵ in Specimen 3. Possibly, these signals could represent the damage mode responsible for the final failure of the test specimens. Theoretically, these signals could be generated from the cracks which culminated around the cenosphere failed by the removal of these spherical particles from the resin surface. Perhaps, additional analysis using some other in-situ techniques might validate this hypothesis. Nonetheless, the AE signals, which are classified based on their ToA and peak frequencies can identify the di ff erent damage evolution stages in the syntactic foams under tensile loading. Perhaps, an additional in-situ technique may be useful in associating specific failure modes to each cluster of AE signals. It must be noted that the main objective of this research work is to validate whether the ToA estimated using the proposed method can be used for damage characterization and structural health monitoring. The presented results show that the estimated ToA of the AE signals can potentially be used in structural health monitoring applications. A novel method for estimating the Time of Arrival (ToA) of the Acoustic Emission (AE) signals is proposed in this research work. The proposed method is also applicable to signals with a low signal-to-noise ratio and signals with multiple amplitude peaks. The applicability of the ToA estimated by the proposed method in structural health monitoring applications is validated in this research work. The ToA of the AE signals generated from the tensile tests of cenosphere-reinforced unsaturated polyester syntactic foams are estimated. The estimated ToA, when classified along with the peak frequencies of the AE signals can potentially identify the di ff erent failure modes in test specimens. However, the applicability of this proposed method must be controlled for the AE signals generated from the larger structures. Barile, C., Casavola, C., Pappalettera, G. and Kannan, V.P., 2020. Application of di ff erent acoustic emission descriptors in damage assessment of fiber reinforced plastics: A comprehensive review. Engineering Fracture Mechanics, 235, p.107083. Barile, C., Casavola, C., Pappalettera, G. and Kannan, V.P., 2023. Interpreting the Lempel–Ziv complexity of acoustic emission signals for identi fying damage modes in composite materials. Structural Health Monitoring, 22(3), pp.1708-1720. Burud, N. and Kishen, J.C., 2021. Damage detection using wavelet entropy of acoustic emission waveforms in concrete under flexure. Structural Health Monitoring, 20(5), pp.2461-2475. Carpinteri, A., Xu, J., Lacidogna, G. and Manuello, A., 2012. Reliable onset time determination and source location of acoustic emissions in concrete structures. Cement and concrete composites, 34(4), pp.529-537. Deepthi, M.V., Sharma, M., Sailaja, R.R.N., Anantha, P., Sampathkumaran, P. and Seetharamu, S., 2010. Mechanical and thermal characteristics of high density polyethylene–fly ash cenospheres composites. Materials & Design, 31(4), pp.2051-2060. Ester, M., Kriegel, H.P., Sander, J. and Xu, X., 1996, August. A density-based algorithm for discovering clusters in large spatial databases with noise. In kdd (Vol. 96, No. 34, pp. 226-231). Kitagawa, G. and Akaike, H., 1978. A procedure for the modeling of non-stationary time series. Annals of the Institute of Statistical Mathematics, 30, pp.351-363. Kulkarni, M.B. and Mahanwar, P.A., 2012. E ff ect of methyl methacrylate–acrylonitrile-butadiene–styrene (MABS) on the mechanical and thermal properties of poly (Methyl Methacrylate)(PMMA)-fly ash cenospheres (FAC) filled composites. Journal of Minerals and Materials Characteri zation and Engineering, 11(04), p.365. Sause, M.G., Mu¨ller, T., Horoschenko ff , A. and Horn, S., 2012. Quantification of failure mechanisms in mode-I loading of fiber reinforced plastics utilizing acoustic emission analysis. Composites science and technology, 72(2), pp.167-174. Sedlak, P., Hirose, Y., Enoki, M. and Sikula, J., 2008. Arrival time detection in thin multilayer plates on the basis of Akaike information criterion. Journal of Acoustic emission, 26, pp.182-188. Siracusano, G., Lamonaca, F., Tomasello, R., Garesc`ı, F., La Corte, A., Carn`ı, D.L., Carpentieri, M., Grimaldi, D. and Finocchio, G., 2016. A frame work for the damage evaluation of acoustic emission signals through Hilbert–Huang transform. Mechanical Systems and Signal Processing, 75, pp.109-122. Vimalathithan, P.K. and Vijayakumar, C.T., 2018. Characterization of cenosphere-reinforced vinyl ester composites. Journal of Elastomers & Plastics, 50(2), pp.95-106. 5. Conclusion References