PSI - Issue 41

T.F.C. Pereira et al. / Procedia Structural Integrity 41 (2022) 14–23 Pereira et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Nonetheless, η ≤1 over predic ts P m , in comparison with the benchmark, while the opposite is found for η >1. The maximum deviation between η =0.5 in relation to  =1 is 5.1% ( L O =25 mm). The best results were found for η =1, with a respective maximum difference of 3.1% to  =1 ( L O =25 mm). Finally, the worst match was found for η =2.5, with a maximum offset of 10.9% to  =1 ( L O =25 mm). 4. Conclusions In this work, the influence of the impact CZM parameters on P m of adhesively-bonded CFRP SLJ was evaluated. Initial CZM validation was accomplished with steel SLJ, The P m comparison showed ≈16% offset to the experiments, which was considered acceptable and served as basis for the numerical analysis. Relevant guidelines were found in the subsequent numerical analysis, which enables a deeper knowledge in the modelling accuracy and capacity of CZM for impact joint design: • Mode decoupling: Decoupling the tensile and shear CZM laws leads to non-negligible P m under estimations, and thus this technique is not recommended, although commercial software limitation can prevent application of non standard laws, which do not possess mixed-mode formulations; • CZM shape: For a brittle adhesive, the CZM shape has a negligible effect on P m throughout the tested L O . Bigger differences could be found for ductile adhesives; • Damage initiation criterion: The QUADS criterion was considered the benchmark. Stress-based criteria behave identically and accurately, while strain-based criteria significantly over predict P m and should not be used; • Damage propagation criterion: Differences from the benchmark  =1 (PW propagation criterion) are small for  >1 but significant for  <1. 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