PSI - Issue 77

D.C. Gonçalves et al. / Procedia Structural Integrity 77 (2026) 79–86 Gonçalves et al. / Structural Integrity Procedia 00 (2026) 000 – 000

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(a) (b) Fig. 8. (a) Experimental DCB crack length vs curves; (b) Experimental ENF crack length vs curves.

4. Conclusion In this work, a meshless method, the radial point interpolation method, was applied to predict crack propagation in adhesively bonded joints. The domain of the adhesive joint is discretized into a set of independent field nodes, being nodal connectivity enforced by the overlap of influence domains. The crack tip is propagated through local remeshing of the field nodes around the crack tip, and the RPI shape functions are updated locally at each crack increment. DCB and ENF specimens were manufactured to assess the application of the computational model to Mode I and Mode II applications. The experimental load-displacement curves allow the construction of the resistance curves using distinct methods, permitting the definition of the critical energy release rates in mode I and mode II, which were then considered in the numerical model to implement the critical energy release rate criterion. It was found that the experimental load-displacement curves are accurately predicted using the numerical technique, independently of the data reduction scheme used to calculate the fracture energy in DCB and ENF joints. In the DCB case, the maximum failure load is predicted with less than 2% error compared with the average experimental maximum failure load. In the ENF scenario, using the CBBM technique allowed the prediction of the average experimental maximum failure load with a 2.6% error. Also, the experimental curves employing the measured crack length are well predicted by the numerical model. The meshless algorithm is capable of analyzing the complex behaviour of adhesive joints, even considering relatively sparse nodal discretizations. Smooth stress fields are obtained using the RPIM, the adherend/adhesive interface can be well modelled, and the local remeshing algorithm is efficient. In conclusion, the accurately simulated experimental Mode I and Mode II tests demonstrate the capability of the proposed method, and motivate the extension to more demanding plastic and large deformations adhesive joint applications. Acknowledgements This work has been funded by the Ministério da Ciência, Tecnologia e Ensino Superior through the Fundação para a Ciência e a Tecnologia (Portugal), under project funding ‘2022.13841.BD’ (https://doi.org/10.54499/2022.13841.BD) , ‘POCI -01-0145-FEDER- 028351’, and ‘SFRH/BD/147628/2019’. Additionally, the authors acknowledge the funding provided by the Associated Laboratory for Energy, Transports and Aeronautics (LAETA), under project ‘UIDB/50022/2020’. References

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