Experimental and Numerical Investigation of Second Mode of Failure in Unlike End Notch Flexure Samples

Document Type : Research Article

Authors

Department of Mechanical Engineering, Quchan University of Technology, Quchan, Iran

Abstract

Localized lamination using composites is one of the effective solutions to repair damaged metallic pipelines. The connection of composite repair to the metal substructure in this method is one of the most important design parameters. Therefore, deriving the important parameters at the junction will help engineers in designing and predicting the interlaminar crack initiation and propagation at the composite/metal interface. In this paper, to investigate the second mode of failure in this method, the strain energy release rate is calculated experimentally and numerically in a steel/composite bond. According to an experimental standard for calculating the second mode strain energy release rate, ASTM-D7905, experimental tests are accomplished for three symmetric and asymmetric unlike end-notched flexure specimens and a relationship for the thickness of each material to have symmetric specimens is proposed. To validate the thickness calculation relationship, the finite element modeling of unlike samples using virtual crack closure technique is used which indicates the good agreement of experimental and numerical results. Comparing the experimental results showed that the strain energy release rate of symmetric samples is more than asymmetric ones and about 1.6 times as large.

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[1]  J.R. McCready, M. Knofczynski, M.W. Keller, Sur- vivability of composite repairs of piping subjected to flexural loads, International Journal of Pressure Ves- sels and Piping, 152 (2017) 7-14.
[2]  J.S. Kim, K.D. Bae, C. Lee, Y.J. Kim, W.S. Kim, I.J. Kim, Fatigue life evaluation of composite material sleeve using a residual stiffness model, International Journal of Fatigue, 101 (2017) 86-95.
[3]  J.J. Denney, S. Mall, Characterization of disbond ef- fects on fatigue crack growth behavior in aluminum plate with bonded composite patch, Engineering Frac- ture Mechanics, 57(5) (1997) 507-525.
[4]  J. J. Schubbe, S. Mall, Investigation of a cracked thick aluminum panel repaired with a bonded composite patch, Engineering Fracture Mechanics, 63.3 (1999) 305-323.
[5]  D.C. Seo, J.J. Lee, Fatigue crack growth behavior of cracked aluminum plate repaired with composite patch, Composite Structures, 57(1-4) (2002) 323-330.
[6]  J. Liu, M. Qin, Q. Zhao, L. Chen, P. Liu, J.Gao, Fa- tigue performances of the cracked aluminum-alloy pipe repaired with a shaped CFRP patch, Thin-Walled Structures, 111 (2017) 155-164.
[7] R. Brighenti, Patch repair design optimisation for frac- ture and fatigue improvements of cracked plates, In- ternational Journal of Solids and Structures, 44(3- 4)(2007) 1115-1131.
[8]  A.M. Kumar, S.A. Hakeem, Optimum design of sym- metric composite patch repair to centre cracked metal- lic sheet, Composite Structures, 49(3) (2000) 285- 292.‏
[9]  R. Jones, S. Barter, L. Molent, S. Pitt, Crack patching: an experimental evaluation of fatigue crack growth, Composite structures, 67(2) (2005) 229-238.
[10]    V.Sabelkin, S. Mall, J. B. Avram, Fatigue crack growth analysis of stiffened cracked panel repaired with bonded composite patch, Engineering Fracture Mechanics, 73(11) (2006) 1553-1567.
[11]   V.A. Karatzas, E.A. Kotsidis, N.G. Tsouvalis, Ex- perimental fatigue study of composite patch repaired steel plates with cracks, Applied Composite Materials, 22(5) (2015) 507-523.‏
[12]  E.F. Rybicki, M.F. Kanninen, A finite element calcu- lation of stress intensity factors by a modified crack closure integral, Engineering Fracture Mechanics, 9 (1977) 931–938.
[13]  K.N. Shivakumar, P.W. Tan, J.C. Newman, A virtual crack-closure technique for calculating stress intensity factors for cracked three dimensional bodies, Interna- tional Journal of Fracture, 36 (1988) 43–50.
[14]  P.S. Valvo, A physically consistent virtual crack clo- sure technique for I/II/III mixed-mode fracture prob- lems, Procedia Materials Science, 3 (2014) 1983- 1987.
[16]  M.F.S.F. de Moura, R.D.S.G. Campilho, J.P.M. Gon- çalves, Equivalent crack based analyses of ENF and ELS tests, Engineering Fracture Mechanics, 75(9) (2008) 2584-2596.
[17]   B.R.K. Blackman, A.J. Kinloch, M. Paraschi, The determination of the mode II adhesive fracture resis- tance, GIIc, of structural adhesive joints: an effective crack length approach, Engineering Fracture Mechan-ics, 72 (2005) 877–97.
[18]  B.R.K. Blackman, A.J. Brunner, J.G. Williams, Mode II fracture testing of composites: a new look at an old problem, Engineering Fracture Mechanics, 73 (2006) 2443–2455.
[19]  M. F. S. F. De Moura, R. D. S. G. Campilho, J. P. M. Gonçalves, Pure mode II fracture characterization of composite bonded joints, International Journal of Sol- ids and Structures, 46(6) (2009) 1589-1595.‏
[20]  A. Argüelles, J. Viña, A. Fernández-Canteli, I. Viña, J. Bonhomme, Influence of the matrix constituent on mode I and mode II delamination toughness in fiber- reinforced polymer composites under cyclic fatigue, Mechanics of materials, 43(1) (2011) 62-67.‏
[21]  V. Mollón, J. Bonhomme, A. Argüelles, J. Viña, In- fluence of the crack plane asymmetry over GII results in carbon epoxy ENF specimens, Composite Struc- tures, 94(3) (2012) 1187-1191.
[22]  R. Panduranga, K. Shivakumar, Mode-II total fatigue life model for unidirectional IM7/8552 carbon/epoxy composite laminate, International Journal of Fatigue, 94 (2017) 97-109.
[23]  ASTM, D7905/D7905M: Standard test method for mode II interlaminar fracture toughness of unidirec- tional fiber-reinforced polymer matrix composites, American Standard of Testing Methods, Vol. 4, pp. 1-18, 2014. doi: 10.1520/D7905_D7905M-14.
[24]  Reddy JN. Mechanics of laminated composite plates and shells. 2nd ed. CRC Press; 2004.
[25]  F. Asgari Mehrabadi, Fracture Mechanic Analysis In Adhesive Composite/Aluminum Joints, MSc Thesis, University of Tabriz, Mechanical Engineering Depart- ment, September 2011.
[26]  A. Kariman Moghadam, S. Rahnama, S. Maleki, Ex- perimental and numerical investigation of crack growth in adhesive bonding of two composites plates under mode I, Modares Mechanical Engineering, 16(5) (2016) 271-280. (in Persian)
[27]  W.S. Kim, J.J. Lee, Fracture characterization of inter- facial cracks with frictional contact of the crack sur- faces to predict failures in adhesive-bonded joints, Engineering Fracture Mechanics, 76 (2009) 1785– 1799.
[28]  R. Krueger, Virtual crack closure technique: history, approach, and applications, Applied Mechanics Re- views, 57(2) (2004) 109-143.‏