PSI - Issue 47

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

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Regarding the values of the governing parameters referring to the aged conditions with desorption, it is worth noting how the mechanical properties are almost completely recovered. The degradation of the GFRP (about 50%), in terms of the Young modulus, is in accordance with the previous results reported in current literature where the GFRP elements were immersed in seawater and tap water for a long time to evaluate the ageing influence on the mechanical properties. The reduction of the mechanical properties was attributed to the effects of swelling and plasticization of the matrix and degradation at the fiber/matrix interface, induced by prolonged immersion in water. In Figures 12 and 13, the P- δ curves with the absorption phenomenon only, relative to the SLJs with SikaDur 30 and Araldite respectively, are depicted. While, in Figure 14, the P- δ curves with the desorption phenomenon, relating to the SLJs with Araldite only, are depicted. A perfect agreement between the numerical and experimental results is highlighted.

Fig. 12. P- δ curves for SLJ with SikaDur30: a) unaged condition; b) aged condition in tap water (absorption only); c) aged condition in sea water (absorption only).

Fig. 13. P- δ curves for SLJ with Araldite: a) unaged condition; b) aged condition in tap water (absorption only); c) aged condition in sea water (absorption only).