PSI - Issue 18

G. Quino et al. / Procedia Structural Integrity 18 (2019) 507–515

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G. Quino et. al/ Structural Integrity Procedia 00 (2019) 000–000

Fig. 4. Algorithm of the numerical experiment with Weibull distribution of apparent strengths.

The acoustic measurement analysis was run with a threshold of 2% of the maximum signal amplitude. As a result, peaks were identified across the whole waveform as shown with circular markers in Fig. 5. It can be observed that the SNR is appropriate to clearly identify the SM events, hence the technique shows the potential to capture the progression of failure.

Fig. 5. Peaks detected in the sound waveform. The cumulative number of broken fibres is plotted in Fig. 6 along with the time history of load during the test. It can be observed that the cumulative number tends to saturate at ܰ ൌ ͺͲͲ . For the numerical experiment, N was then substituted in equations (6) and (7). Subsequently, the apparent strengths were reconstructed with Equation (8).