PSI - Issue 54

I.R.S. Araújo et al. / Procedia Structural Integrity 54 (2024) 406–413 Araújo et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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4. Conclusions The aim of this work was to carry out a numerical XFEM study to predict the tensile strength of scarf adhesive joints as a function of  and the adhesive type. The numerical study focused on analyzing the damage variable and evaluating P m , which were compared to experimental data. Experimentally, it was observed that decreasing  exponentially increases P m due to more uniform stress distributions but mostly increase of shear-resistant area between the adherends. The AV138 held the highest P m for all  , mainly due to the short stress gradients along the adhesive layer, in which case a strong but brittle adhesive provides better results than more ductile yet less strong adhesives. The damage variable analysis at P m showed that increasing  gives improved uniformity of damage throughout the adhesive layer. Among the adhesives, it was found that increasing the stiffness increases the magnitude of the damage, which is concentrated in smaller areas at the ends of the bond. On the other hand, increasing the ductility of the adhesive allows for a more uniform distribution of damage at P m . Comparison with experimental P m revealed satisfactory results since, in general, the XFEM was able to predict P m values close to the experiments. However, in the scarf joint with  =3.43º there is a larger difference, of -20.3%, between the XFEM predictions and the experiments. It was possible to confirm the XFEM capacity in predicting P m of scarf joints, and that this technique can be used with confidence in the design of adhesive joints with complex geometry that require mixed-mode analysis of the adhesive. References Abaqus® (2013). Documentation. D. Systèmes. Vélizy-Villacoublay. Alves, D. L., Campilho, R. D. S. G., Moreira, R. D. F., Silva, F. J. G. and da Silva, L. F. M., 2018. 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