PSI - Issue 77

6

Muhammad Jahanzeb Zia et al. / Structural Integrity Procedia 00 (2026) 000–000

Muhammad Jahanzeb Zia et al. / Procedia Structural Integrity 77 (2026) 111–118

116

1

Point P6 Point P5 Point P6 Point P5

Point P6 Point P5 Point P6 Point P5

0.9

0.9

0.8

0.8

0.7

0.7

Point P6 Point P5

0.6

0.6

0.5

0.5

0.4

0.4

0.3

0.3 Damage Index

Damage Index

0.2

0.2

0.1

0.1

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 Time (s) 0

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 Time (s) 0

Fig. 3. (a) Matrix damage distribution at 0.08 s and points used for measurements; (b) Matrix cracking evolution and fibre breakage at points P5 and P6 (c).

0.6

0.5

0.4

0.3

0.2

0.1

0

Displacement (mm)

-0.1

-0.2

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

Time (s)

Fig. 4. Time waveform of displacement during damage at point P3.

(a)

(b)

Fig. 5. Spectrogram of instance at 0.22 s (a) and 0.38 s (b) for point P3. Colour bars indicate intensity in dB.

The spectrograms shown in Fig. 5a and Fig. 5b were compared with the experimentally determined frequency ranges reported by Han et al. (2020), where matrix cracking was observed in the range of 40–80 kHz and fibre breakage within 120–200 kHz. The numerical results obtained in this study demonstrated close agreement with these experimentally established values.