PSI - Issue 52

Angela Russo et al. / Procedia Structural Integrity 52 (2024) 535–542 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Figure 11. Results comparison.

4. Conclusions In this paper, a parametric investigation on the delamination propagation of a single stiffened panel has been presented. Three different configurations have been considered, characterized by different initial debonded area length. The numerical analyses have been performed using the SMXB approach, based on the VCCT, and characterized by both time step and mesh independency. The numerical results demonstrate that the damage behaviour of the structure is significantly influenced by the initial delamination length. In particular, the maximum load decreases with increasing initial delamination length. Configurations with higher initial delamination length tend to have a more gradual and stable propagation, allowing for greater control and predictability. Research into this area is of the utmost importance, as it will provide a foundation for the development of more efficient design strategies of structures able to withstand delamination damage. References [1] Russo, A., Palumbo, C., Riccio, A., 2023. The role of intralaminar damages on the delamination evolution in laminated composite structures. Heliyon 9(4), art. no. e15060. DOI: 10.1016/j.heliyon.2023.e15060 [2] Kupski, J., Teixeira de Freitas, S., 2021. Design of adhesively bonded lap joints with laminated CFRP adherends: Review, challenges and new opportunities for aerospace structures. Composite Structures 268, 113923. DOI: 10.1016/j.compstruct.2021.113923 [3] Russo, A., Riccio, A., Palumbo, C., Sellitto, A., 2023. Fatigue driven delamination in composite structures: Definition and assessment of a novel fracture mechanics based computational tool. International Journal of Fatigue 166, art. no. 107257. DOI: 10.1016/j.ijfatigue.2022.107257 [4] Mi, Y., Crisfield, M.A., Davies, G.A.O., Hellweg, H.-B., 1998. Progressive delamination using interface elements. Journal of Composite Materials 32(14), 246 – 1272. DOI: 10.1177/002199839803201401 [5] Reeder, J.R., Crews, J.H. Jr., 1990. Mixed-mode bending method for delamination testing. AIAA Journal 28(7), 1270 – 1276. DOI: 10.2514/3.25204 [6] Riccio, A., Russo, A., Sellitto, A., Toscano, C., Alfano, D., Zarrelli, M., 2020. Experimental and numerical assessment of fibre bridging toughening effects on the compressive behaviour of delaminated composite plates. Polymers 12(3), art. no. 554, pp. 1 – 20. DOI: 10.3390/polym12030554 [7] Riccio, A., Castaldo, R., Palumbo, C., Russo A., 2023. Delamination Effect on the Buckling Behaviour of Carbon – Epoxy Composite Typical Aeronautical Panels. Applied Sciences (Switzerland) 13(7), art. no. 4358. DOI: 10.3390/app13074358 [8] Krueger, R., 2004. Virtual crack closure technique: History, approach, and applications. Applied Mechanics Reviews 57(1-6), 109-143. DOI: 10.1115/1.1595677 [9] Russo, A., Zarrelli, M., Sellitto, A., Riccio, A., 2019. Fiber bridging induced toughening effects on the delamination behavior of composite stiffened panels under bending loading: A numerical/experimental study. Materials 12(15), art. no. 2407. DOI: 10.3390/ma12152407 [10] Release 18.1, Help System. ANSYS, Inc.: Canonsburg, PA, USA, August