PSI - Issue 47

15

Francesco Ascione et al. / Procedia Structural Integrity 47 (2023) 826–841 Author name / Structural Integrity Procedia 00 (2019) 000–000

840

Fig. 17. Interface laws for all points were shear strength reached the limit value: a) SikaDur30; b) Araldite

4. Conclusions In this paper, the numerical study of the hygrothermal effects on the strength and stiffness of two commercial epoxy resins previously experimentally tested was presented. The two resins were cured at the ambient temperature (about 23°C) being the most frequent one for civil engineering applications and conditioned in sea water and tap water at the temperature of 30°C. The experimental results obtained demonstrated that after the absorption period, the strength and stiffness of the resins decreased due to a plasticization phenomenon, while after the desorption period their mechanical properties become similar to those relative to the unaged condition. The experimental results obtained were compared with those of a numerical modelization, where a bilinear interfacial law was adopted. The numerical model was able to take into account the variation, in terms of shear strength and relative displacement (sliding) between the adherents, due to absorption and desorption phenomenon. The agreement with the experimental results was perfect.

References

Abbey, K.J. Advances in epoxy adhesives. Adv. Struct. Adhes. Bond., Woodhead Publishing Limited 2010; 20–34. Ascione, F.; Granata, L.; Guadagno, L.; Naddeo, C. Hygrothermal durability in terms of mode II fracture energy of epoxy adhesives used in civil structural applications. Compos Struct 2021; 265, 113591 .