PSI - Issue 66

B. (Bo) van Schuppen et al. / Procedia Structural Integrity 66 (2024) 412–418 Author name / Structural Integrity Procedia 00 (2025) 000–000

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4. Results The broken wire electronic binary sensor method successfully detects short cracks. A few examples of these cracks are visualized in Fig. 4. All cracks are of a length of < 1 mm. For specimen D7, due to the debonding of the wire, the crack was not detected on time, leading to the formation of a larger crack of length larger than 10 mm.

(c) specimen D4

(a) specimen B4

(b) specimen A5

Fig. 4. Detected cracks by the broken wire binary sensor

The behavior of the specimens is quantified using the elongation measured by the LVDT positioned across the holes, as explained in Section 2. The force vs. elongation curves are plotted in Fig. 5 for all cracked and uncracked specimens. For specimens D2 and D3, the malfunctioning of the LVDT did not allow reporting of the load-elongation curve, however the load at fracture is correctly recorded. The ultimate loads are reported in Table . This table also reports the ratio of the experimental failure load over the resistance calculated with Equation 4. For specimens containing a crack, the ultimate load and the ratio of the experimental failure load over the resistance calculated with Equation 4, are shown in Table 1.

(a) Type A

(b) Type B

(c) Type D

Fig. 5. Force vs Elongation curves for the three types of specimens