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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Table 1. Experimental results and comparison with predicted resistance Specimen ID A net (mm 2 ) N u (kN) N u,test (kN) N u,test /N u (-) A1 731,4 283,7 327,4 1,15 A2 735,9 285,4 325,6 1,14 A3 745,8 289,3 326,0 1,13 A4 736,3 285,6 322,0 1,13 A5 729,4 282,9 319,0 1,13 B1 737,4 286,0 312,0 1,09 B2 737,5 286,1 313,7 1,10 B3 740,4 287,2 313,5 1,09 B4 732,0 283,9 309,2 1,09 B5 727,0 282,0 307,0 1,09 D1 695,7 269,9 293,8 1,09 D2 701,9 272,3 291,9 1,07 D3 697,9 270,7 293,8 1,09 D4 694,3 269,3 277,2 1,03 D5 694,2 269,3 293,7 1,09 D6 683,0 264,9 290,4 1,09 D7 689,8 267,6 230,3 0,86

The ratio of the experimental resistance over the calculated resistance with the resistance formula for all the tested specimens is shown in Fig. 6. An outlier is seen for specimen D7, for which a crack longer than 10mm is present. Generally, it appears that the presence of short cracks does neither affect the ultimate load nor the deformation capacity of the specimens. 0,80 0,85 0,90 0,95 1,00 1,05 1,10 1,15 1,20 A1 A2 A3 A4 A5 B1 B2 B3 B4 B5 D1 D2 D3 D4 D5 D6 D7 Nu,test/Nu [ ‐ ] Specimen ID 5. Prediction of the failure assessment diagram The failure assessment diagram is used to predict the reduction in failure load due to the presence of cracks for the same specimen geometries. The type of cracks observed are mostly corner cracks nucleating at the edges of the hole of circular shape, hence this crack configuration is assumed to determine the reduction in failure load. Additionally, for the determination of K mat , using Equation 5 the value of the temperature T 27J is considered as prescribed for S275 steel grade in part 1-10 of the Eurocode 3 CEN (2005b), i.e. T 27J = 20 ◦ C. The FAD predicts, independent from the specimen type, a marginal reduction in failure load, i.e. <5%, for cracks having lengths up to 0.3 mm. This is further reduced to about 80% for ten times longer cracks, i.e. ~3 mm. Qualitatively, these findings are in line with the experimental results, leading to a slightly conservative prediction of the failure load. This is potentially given by the use of Option 1 FAD, which is known to be conservative, and the approximate estimation of the plastic collapse load obtained using the reference stress approach provided in the British Standard 7910, BSI (2013). Fig. 6. Ratio of the experimental resistance over the calculated resistance, for un-cracked and cracked specimens