Proposta de trabalhos futuros

Nesta secção, são apresentadas propostas que poderão ser objeto de futuros trabalhos, nomeadamente:

o Realização de um maior número ensaios para os provetes ENF, uma vez que as cinco unidades ensaiadas não são um número plausível de amostras. Aconselha-se a utilização única dos provetes VM,uma vez que apresentaram um comportamento mais

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o No ensaios ENF, procurar calibrar experimentalmente a flexibilidade para vários comprimentos de fenda e mantendo o vão constante.

o Realização de ensaios para as ligações DLJ, de modo a obter-se uma maior amostragem de resultados para construção de uma curva S-N estatisticamente mais representativa.

o Realização dos mesmos ensaios com uma frequência de ensaio de 40 Hz, velocidade de ensaio utilizada na ficha técnica do adesivo. Se possível, ensaiar provetes DCB com dimensões normalizadas, para que se possa utilizar o método CBBM na sua análise, por exemplo.

o Estudo dos ensaios pelo método de Correlação Digital de Imagem, para se avaliar os processos de iniciação e progressão das fendas de fadiga e, de um modo geral, fornecer informação de campo importante na análise de resultados.

o Usando os resultados gerados, adaptar modelos de dano coesivo para fadiga e validar modelo com as juntas DLJ.

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Science and Technology, vol. 25, pp. 2881–2895.

[3] Jen, Y. -M. 2012, ‘Fatigue life evaluation of adhesively bonded scarf joints’,

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[13] Markolefas, S. I. e Papathanassiou, T. K. 2009, ‘Stress redistributions in adhesively bonded double-lap joints, with elasticperfectly plastic adhesive behavior, subjected to axial lapshear cyclic loading’, International Journal of Adhesion and Adhesives, vol. 29, no. 7, pp. 737–744.

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[22] Silva, L. F. M. da, Ferreira, N. M. A. J., Richter-Trummer, V., e Marques, E. A. S. 2010, ‘Effect of grooves on the strength of adhesively bonded joints’, International Journal of

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[23] Gomatam, R. R. e Sancaktar, E. 2005, ‘Effects of various adherend surface treatments on fatigue behavior of joints bonded with a silver-filled electronically conductive adhesive’,

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International Journal of Fatigue, vol. 32, no. 8, pp. 1278–1288.

[25] Solana, A. Graner, Crocombe, A. D. e Ashcroft, I. A. 2010, ‘Fatigue life and backface strain predictions in adhesively bonded joints’, International Journal of Adhesion and

Adhesives, vol. 30, no. 1, pp. 36–42.

[26] Imanaka, M., Taniguchi, M., Hamano, T. e Kimoto, M. 2005, ‘Fatigue life estimation of adhesively bonded scarf joints based on a continuum damage mechanics model’, Polymers

and Polymer Composites, vol. 13, no. 4, pp. 359–370.

[27] Shenoy, V., Ashcroft, I. A., Critchlow, G. W., Crocombe, A. D. e Wahab, M. M. A. 2009, ‘Strength wearout of adhesively bonded joints under constant amplitude fatigue’,

International Journal of Fatigue, vol. 31, no. 5, pp. 820–830.

[28] Quaresimin, M. e Ricotta, M. 2006, ‘Life prediction of bonded joints in composite materials’, International Journal of Fatigue, vol. 28, no. 10, pp. 1166–1176.

[29] Wahab, M. M. A., Ashcroft, I. A., Crocombe, A. D., e Joussot, L. 2003, ‘Lifetime prediction for fatigue damage in bonded joints’, Key Engineering Materials, vol. 245-246, pp. 43–50.

[30] Imanaka, M., Hamano, T., Morimoto, A., Ashino, R. e Kimoto, M. 2003, ‘Fatigue damage evaluation of adhesively bonded butt joints with a rubber-modified epoxy adhesive’,

Journal of Adhesion Science and Technology, vol. 17, no. 7, pp. 981–.

[31] Wahab, M. M. A., Hilmy, I., Ashcroft, I. A. e Crocombe, A.D. 2010, ‘Evaluation of fatigue damage in adhesive bonding: part 1: bulk adhesive’, Journal of Adhesion Science and

Technology, vol. 24, no. 2, pp. 305–324.

[32] Wahab, M. M. A., Hilmy, I., Ashcroft, I. A. e Crocombe, A. D. 2010, ‘Evaluation of fatigue damage in adhesive bonding: part 2: single lap joint’, Journal of Adhesion Science and

Technology, vol. 24, no. 2, pp. 325–345.

[33] Shenoy, V., I. Ashcroft, A., Critchlow, G. W., Crocombe, A. D. e Wahab, M. M. A. 2009, ‘An investigation into the crack initiation and propagation behaviour of bonded singlelap joints using backface strain’, International Journal of Adhesion and Adhesives, vol. 29, no. 4, pp. 361–371.

[34] Crocombe, A. D., Ong, C. Y., Chan, C. M., Wahab, M. M. A. e Ashcroft, I. A. 2002, ‘Investigating fatigue damage evolution in adhesively bonded structures using backface strain measurement’, The Journal of Adhesion, vol. 78, no. 9, pp. 745–776.

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[37] Pirondi, A. e Moroni, F. 2010, ‘A progressive damage model for the prediction of fatigue crack growth in bonded joints’, The Journal of Adhesion, vol. 86, no. 5-6, pp. 501– 521.

[38] Azari, S., Papini, M., Schroeder, J. A. e Spelt, J. K. 2010, ‘The effect of mode ratio and bond interface on the fatigue behavior of a highly-toughened epoxy’, Engineering

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[39] Pirondi, A. e Moroni, F. 2009, ‘An investigation of fatigue failure prediction of adhesively bonded metal/metal joints’, International Journal of Adhesion and Adhesives, vol. 29, no.8, pp. 796–805.

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[43] Du, Y. e Shi, L. 2014, ‘Effect of vibration fatigue on modal properties of single lap adhesive joints’, International Journal of Adhesion & Adhesives, vol. 53, pp. 72–79.

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