PSI - Issue 10

D. Mastrogiannis et al. / Procedia Structural Integrity 10 (2018) 319–325 D. Mastrogiannis et al. / Structural Integrity Procedia 00 (2018) 000 – 000

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Fig. 3. From top to bottom: The amplitude of Acoustic Emission (AE) signals produced during the application of mechanical load in dB and mV; the corresponding Pressure Stimulated Currents (PSC); the amplitude of the applied mechanical load.

contrary, when someone is using as a fitting function a power-law form with log periodic corrections, i.e., Eq.(1), the results are apparently more accurate for both cases of the AE and PSC energy released. This can be verified by comparing the red solid curves, indicating the fitting by Eq.(1), with the blue solid curves in Fig.4.

4. Conclusions

Since now the application of log-periodic power law models has been limited to cases of laboratory experiments of deforming and fracturing well-defined specimens of solid materials. This is the first time that such a model is being applied on the AE signals originating from a complex, man-made structure, like the epistyle of Parthenon. Besides that, the novelty of this work also resides on the fact that the log-periodic power law model has been applied on data that described the amplitude of PSC that are also produced due to the deformation procedure of a material. It is apparent that the log periodic power law model can be successfully applied in the case of more complex structural setups and it can probably be used as a tool of studying the behavior of such structures, in cases where the simple power law model fails to do so. An interesting point is that the signals of PSC also provide data which can be fitted by this mathematical model. The importance of using a log periodic power law is apparent through the com parison with the corresponding power laws; log periodic power law provides more accurate modeling. This opens up