Raul D.S.G. Campilho^1*, Marcelo F.S.F. de Moura^2*, Joaquim J.M.S. Domingues^3**

*Departamento de Engenharia Mecânica e Gestão Industrial, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal

**Departamento de Engenharia Mecânica, Instituto Superior de Engenharia do Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto, Portugal

¹dem05004@fe.up.pt, ²mfmoura@fe.up.pt, ³jsd@isep.ipp.pt

ABSTRACT: The present work consists on an experimental and numerical study of the tensile residual strength of single-strap adhesively bonded repairs made of carbon-epoxy composites. It is considered the failure mode, the remote failure stress and the equivalent stiffness of the repairs, as a function of the overlap length and patch thickness. In order to numerically simulate damage onset and growth, leading to the repair failure, a mixed-mode cohesive damage model based on the indirect use of Fracture Mechanics was used. Good agreement between experimental and numerical results was found, concerning the studied parameters.

Keywords: Repair, Composite, Adhesive joint, Finite Element Method.

RESUMO: O presente trabalho consiste num estudo experimental e numérico relativo à resistência residual à tracção de reparações adesivas por sobreposição simples de laminados de carbono-epóxido. São considerados o modo de rotura, a tensão de colapso e a rigidez equivalente das reparações em função do comprimento de sobreposição e da espessura do remendo. Para simular numericamente o início e crescimento do dano, conducentes à rotura das reparações, é utilizado um modelo de dano coesivo em modo misto baseado no uso indirecto da mecânica da fractura. Obteve-se boa concordância entre os resultados numéricos e os experimentais, no que diz respeito aos parâmetros estudados.

Palavras chave: Reparação, Compósito, Junta adesiva, Método dos Elementos Finitos.

Texto completo disponível apenas em PDF.

Full text only available in PDF format.

REFERÊNCIAS

[1] Hu FZ, Soutis C. Strength prediction of patch repaired CFRP laminates loaded in compression. Comp. Sci. Technol. 2000;60:1103-1114.        [ Links ]

[2] Soutis C, Duan DM. Compressive behaviour of CFRP laminates repaired with adhesively bonded external repairs. Comp. Struct. 1999;45:289-301.

[4] Gonçalves JPM, de Moura MFSF, de Castro PMST. A three-dimensional finite element model for stress analysis of adhesive joints. Int. J. Adh. Adhesives 2002;22:357-365.

[5] Campilho RDSG, de Moura MFSF, Domingues JJMS. Modelling single and double-lap repairs on composite materials. Comp. Sci. Technol. 2005;65:1948-1958.

[6] de Moura MFSF, Daniaud R, Magalhães AG. Simulation of mechanical behaviour of composite bonded joints containing strip defects. Int. J. Adh. Adhesives 2006;26:464-473.

[7] Ávila AF, Bueno PO. An experimental and numerical study on adhesive joints for composites. Comp. Struct. 2004;64:531-537.

[8] Zou GP, Shalin K, Taheri F. An analytical solution for the analysis of symmetric composite adhesively bonded joints. Comp. Struct. 2004;65:499-510.

[9] Mortensen F, Thomsen OT. Analysis of adhesive bonded joints: a unified approach. Comp. Sci. Technol. 2002;62:1011-1031.

[10] Magalhães AG, de Moura MFSF, Gonçalves JPM. Evaluation of stress concentration effects in single-lap bonded joints of laminate composite materials. Int. J. Adh. Adhesives 2005;25:313-319.