PSI - Issue 64

Veronica Bertolli et al. / Procedia Structural Integrity 64 (2024) 1111–1117 Veronica Bertolli , Tommaso D’Antino, Christian Carloni / Structural Integrity Procedia 00 (2019) 000 – 000

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Where h sp is the distance between the tip of the notch and the top side of the specimen in the mid-span cross section, i.e., h sp = H - a 0 . The nominal strength f L is determined starting from the peak load, or from the highest load value between the interval 0-0.05 mm, F L , applied during the three-point bending test. The nominal strength f L computed for the specimens tested is reported in Table 1. Among the four different values of residual flexural tensile strength required by EN 14651 (European Committee for Standardization (2007)), only f R 1 , corresponding to CMOD 1 =0.5 mm, was computed for all specimens tested. The residual strength f R 2 , corresponding to CMOD 2 =1.5 mm, was computed for specimen groups NBT-5.2-12 and NBT-5.2-15.

Fig. 3   – CMOD curves of a) specimens with microfibers, b) specimens with micro and macrofibers, c) all specimens tested, and d) details of responses of Fig. 3c.

The  N – CMOD curves are reported in Fig. 3a for specimen groups NBT-2.6, NBT-3.9, and NBT-5.2 (with microfibers) and in Fig. 3b for specimen groups NBT-5.2-12 and NBT-5.2-15 (with both micro and macrofibers). Fig. 3c shows a comparison of the responses of all specimens, whereas Fig. 3d provides a detail of Fig. 3c. Values reported in Table 1 and curves depicted in Fig. 3 showed that the addition of microfibers did not seem to provide an