A Strategy for a Robust Design of Cracked Stiffened Panels

Authors: Francesco Caputo, Giuseppe Lamanna, Alessandro Soprano

Abstract:

This work is focused on the numerical prediction of the fracture resistance of a flat stiffened panel made of the aluminium alloy 2024 T3 under a monotonic traction condition. The performed numerical simulations have been based on the micromechanical Gurson-Tvergaard (GT) model for ductile damage. The applicability of the GT model to this kind of structural problems has been studied and assessed by comparing numerical results, obtained by using the WARP 3D finite element code, with experimental data available in literature. In the sequel a home-made procedure is presented, which aims to increase the residual strength of a cracked stiffened aluminum panel and which is based on the stochastic design improvement (SDI) technique; a whole application example is then given to illustrate the said technique.

Keywords: Residual strength, R-Curve, Gurson model, SDI.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1062422

References:

[1] R. Mahnken, "Theoretical, numerical and identification aspects of a new model class for ductile damage" in International Journal of Plasticity, vol. 18, Ed. Amsterdam, NL: Elsevier, 2002, pp. 801-831.
[2] L. Xia, C. F. Shih, J. W. Hutchinson, "A computational approach to ductile crack growth under large scale yielding conditions" in Journal of the Mechanics and Physics of Solids, vol. 43-3, Ed. Amsterdam, NL: Elsevier, 1995, pp. 389-413.
[3] Chabanet, D. Steglich, J. Besson, V. Heitmann, D. Hellmann, W. Brocks, "Predicting crack growth resistance of aluminium sheets" in Computational Materials Science, vol. 26, Ed. Amsterdam, NL: Elsevier, 2003, pp. 1-12.
[4] Kintzel, S. Khan, J. Mosler "A novel isotropic quasi-brittle damage model applied to LCF analyses of Al2024" in International Journal of Fatigue, vol. 32-12, Ed. Amsterdam, NL: Elsevier, 2010, pp. 1948-1959.
[5] J. Faleskog, X. Gao, C. F. Shih, "Cell model for nonlinear fracture analysis — I Micromechanics calibration" in International Journal of Fracture, vol. 89, Ed. Heidelberg, D: Springer, 1998, pp. 355-373.
[6] F. Scheyvaerts, P.R. Onck, C. Teko Diu, T. Pardoen, "The growth and coalescence of ellipsoidal voids in plane strain under combined shear and tension" in Journal of the Mechanics and Physics of Solids, vol. 59-2, Ed. Amsterdam, NL: Elsevier, 2010, pp. 373-397.
[7] L. Gurson, "Continuum theory of ductile rupture by void nucleation and growth: part I - yield criteria and flow rules for porous ductile media" in Journal of Engineering Materials and Technology — T ASME, vol. 99-1, Ed. New York, USA, 1977, pp. 2-15.
[8] V. Tvergaard, "Influence of void nucleation on ductile shear fracture at a free surface" in Journal of the Mechanics and Physics of Solids, vol. 30, Ed. Amsterdam, NL: Elsevier, 1982, pp. 399-425.
[9] J.S Robinson, Presentation on the IDA meeting in Geesthacht 22-23 June 2005, University of Limerick (2005).
[10] F. Caputo, G. Lamanna, A. Soprano, "Stochastic improvement of the residual strength of a stiffened panel" in Key Engineering Materials, vol. 348-349, Ed. Durnten-Zurich, CH: Trans Tech Publications Inc., 2007, pp. 301-304.
[11] C. Zang, M.I. Friswell, J. E. Mottershead, "A review of robust optimal design and its application in dynamics" in Computers and Structures, vol. 83, Ed. Amsterdam, NL: Elsevier, 2005, pp. 315-326.
[12] T. E. Murphy, K. L. Tsui, J. K. Allen, "A review of robust design methods for multiple responses" in Research in Engineering Design, vol. 16, Ed. Heidelberg, D: Springer, 2005, pp. 118-127.
[13] F. Caputo, A. Soprano, G. Monacelli, "Stochastic design improvment of an impact absorber" in Latin American J. of Solids and Structures, vol. 3, Ed. Sao Paulo, BR: Lajss, 2006, pp. 41-53.
[14] Soprano, F. Caputo, "Building a risk assessment procedure" in Structural Durability & Health Monitoring, vol. 2, n. 1, Ed. Duluth GA, USA: Tech Science Press, 2006, pp. 51-68.
[15] R. Citarella, A. Apicella, "Advanced design concepts and maintenance by integrated risk evaluation for aerostructures" in Structural Durability & Health Monitoring, vol. 2, n. 3, Ed. Duluth GA, USA: Tech Science Press, 2006, pp. 183-196.
[16] I. Doltsinis, F. Rau, M. Werner, "Analysis of random systems", Ed. I. Doltsinis, Barcelona, E: CIMNE 2004, pp. 9-149.
[17] E. Armentani, R. Citarella, R. Sepe, "FML Full scale aeronautic Panel under multiaxial fatigue: experimental test and DBEM simulation" in Engineering Fracture Mechanics, vol. 78, Ed. Amsterdam, NL: Elsevier, 2011, pp. 1717-1728.
[18] H. J. ten Hoeve, L. Schra, A. L. P. J. Michielsen, H. Vlieger, "Residual strength test on stiffened panels with multiple-site damage", report n: DOT/FAA/AR-98/53, U.S. Department of Transportation, USA, 1999.
[19] G. Lamanna, F. Caputo, A. Soprano, "Geometrical parameters influencing a hybrid mechanical coupling", in Key Engineering Materials, vol. 525-526, Ed. Durnten-Zurich, CH: Trans Tech Publications Inc., 2012, pp. 161-164.
[20] A. Soprano, F. Caputo, A. Grimaldi, "A numerical Investigation about the effects of the riveting operation on the strength of joints" in Key Engineering Materials, vol. 348-349, Ed. Durnten-Zurich, CH: Trans Tech Publications Inc., 2007, pp. 265-268.
[21] G. Lamanna, F. Caputo, A. Soprano, "Handling of composite-metal interface in a hybrid mechanical coupling", in AIP American Institute of Physics conference proceedings, vol. 1459, Ed. Melville New York, USA: American Institute of Physics, 2012, pp 353-356.
[22] G. Lamanna, F. Caputo, A. Soprano, "Effects of tolerances on the structural behaviour of a bolted hybrid joint", in Key Engineering Materials, vol. 488-489, Ed. Durnten-Zurich, CH: Trans Tech Publications Inc., 2012, pp. 565-568.
[23] G. Lamanna, F. Caputo, A. Soprano, "Numerical modelling and simulation of a bolted hybrid joint", in Structural Durability & Health Monitoring, vol. 7, n. 4, Ed. Duluth GA, USA: Tech Science Press, 2011, pp. 283-296.
[24] G. Lamanna, F. Caputo, F.M. Pannullo, G. De Angelis, "A methodological approach to the tolerance problems during the assembly process of deformable bodies", in Key Engineering Materials, vol. 488-489, Ed. Durnten-Zurich, CH: Trans Tech Publications Inc., 2012, pp. 557-560.
[25] A. S. Gullerud, K. C. Koppenhoefer, A. Roy, R. H. Dodds, jr., B. Healy, S. RoyChowdhury, M. Walters, B. Bichon, K. Cochran, A. Carlyle, J. Sobotka, M. Messner, Warp3D Release 17.3.2 3D Dynamic Nonlinear Fracture analysis of Solids Using Parallel Computers, User and theoretical manual, (University of Illinois), 2012.
[26] F. Caputo, G. Lamanna, A. Soprano, "Numerical investigation on the crack propagation in a flat stiffened panel" in Key Engineering Materials, vol. 324-325, Ed. Durnten-Zurich, CH: Trans Tech Publications Inc., 2006, pp. 1039-1042.
[27] C. Cali, R. Citarella, "Residual strength assessment for a butt-joint in MSD condition" in Advences in Egineering Software, vol. 35, Ed. Amsterdam, NL: Elsevier, 2004, pp. 373-382.
[28] D. Steglich, T. Siegmund, W. Brocks, "Micromechanical modeling of damage due to particle cracking in reinforced metals" in Computational Materials Science, vol. 16, Ed. Amsterdam, NL: Elsevier, 1999, pp. 404-413.
[29] F. Caputo, G. Lamanna, A. Soprano, "The plastic zone size at short cracks tip" in Engineering Fracture Mechanics, Ed. Amsterdam, NL: Elsevier, 2012, doi: 10.1016/j.engfracmech.2012.09.030.
[30] F. Caputo, G. Lamanna, A. Soprano, "An analytical formulation for the plastic deformation at the tip of short cracks" in Procedia Engineering, vol. 10, Ed. Amsterdam, NL: Elsevier, 2011, pp. 2988¬2993.