Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-22T11:16:47.609Z Has data issue: false hasContentIssue false

Predicting impact damage of composite stiffened panels

Published online by Cambridge University Press:  04 July 2016

G. A. O. Davies
Affiliation:
Department of Aeronautics, Imperial College, London, UK
X. Zhang
Affiliation:
College of Aeronautics, Cranfield University, Bedford, UK

Abstract

This paper addresses the problem of the complex nature of low velocity impact damage in fabricated structures made of laminated carbon-epoxy composites. The structures chosen are stiffened compression panels since these are the most vulnerable to delamination and debonding. Four ‘top-hat’ stiffened panels were tested and predicted using a dynamic finite element code. The panels all had considerable postbuckling strength so the impact sites were carefully chosen to inflict maximum loss of strength. It was shown that the threshold energy for onset of delamination can be predicted using a dynamic finite element code. The amount of delamination or debonding is also predicted using a crude strength-based criterion, which seems to work only because the maximum impact force is a transient phenomenon of short duration.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2000 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Dorey, G. Impact damage in composites — development, consequences and prevention, Proc of 6th Int Conf on Composite Materials and 2nd European Conf on Composite Materials, 1987, Pub Elsevier Applied Science, pp 3.13.26.Google Scholar
2. Greszczuk, L.B. Damage in composite panels due to low velocity impact, Impact Dynamics, Zukas, Z.A. (Ed), 1982, J. Wiley.Google Scholar
3. Prichard, J.C. and Hogg, P.J. The role of impact damage in postimpact compression testing, Composites, 1990, 21, pp 503511.Google Scholar
4. Bauer, J.G. and Neumeier, R. Allowable compression strength for CFRP-components of fighter aircraft determined by CAI-test, AGARD 74th Structures and Materials Meeting: Debonding/Delamination of Composites, Patras, May 1992.Google Scholar
5. Wiggenraad, J.F.M., Zhang, X. and Davies, G.A.O. Impact damage prediction and failure analysis of heavily loaded, blade-stiffened composite wing panels, Comp Struc, 1999, 45, pp 81103.Google Scholar
6. Jegley, D.C. Study of compression-loaded and impact-damaged structurally efficient graphite-thermoplastic trapezoidal-corrugation sandwich and semisandwich panels, NASA Technical Paper 3264, Langley Research Centre, 1992.Google Scholar
7. Davies, G.A.O. and Zhang, X. Impact damage prediction in carbon composite structures, Int J Impact Eng, 1995, 16, pp 149170.Google Scholar
8. Davies, G.A.O. and Robinson, P. Predicting failure by debonding/ delamination, AGARD 74th Structures and Materials Meeting: Debonding/Delamination of Composites, Patras, 24–29 May 1992.Google Scholar
9. Davies, G.A.O., Zhang, X., Zhou, G. and Watson, S. Numerical modelling of impact damage, Composites, 1994, 25, pp 342–250.Google Scholar
10. Hitchings, D. FE77 general purpose modular finite element system for static and dynamic, linear and non-linear analysis, Dept of Aeronautics, Imperial College, 1993.Google Scholar
11. Specht, S., Stevens, K.A. and Davies, G.A.O. Postbuckling of composite structures, Progress Report 3, Contract AEST 4852, Department of Aeronautics, Imperial College, April 1995.Google Scholar
12. Zhang, X., Hitchings, D. and Davies, G.A.O. Failure of realistic compression panels, Supplementary Report, Contract FRN1c/F32, Department of Aeronautics, Imperial College, January 1997.Google Scholar
13. Chang, F.-K. and Chang, K.-Y. Post-failure analysis of bolted composite joints in tension or shear-out mode failure, J Comp Mat, 1997, 21, pp 809833.Google Scholar
14. Chang, F.-K. and Chang, K.-Y. A progressive damage model for laminated composites containing stress concentrations, J Comp Mat, 1987, 21, pp 834855.Google Scholar
15. Davies, G.A.O., Zhang, X. and Hitchings, D. Modelling impact damage in laminated composites, NAFEMS World Congress ’97 on Design, Simulation and Optimisation, Stuttgart, 9–11 April 1997; Conference proceedings, pp 12161231, Pub NAFEMS.Google Scholar
16. Mindlin, R.D. Influence of rotary inertia and shear on flexural motion of isotropic elastic plates, J Appl Mech, 1951, 18, pp 3138.Google Scholar