Advertisement

Impact and Residual Strength Assessment Methodologies

  • Luise Kärger
  • Jens Baaran
  • Anja Wetzel
Chapter
Part of the Research Topics in Aerospace book series (RTA)

Abstract

In this chapter, efficient methodologies to evaluate impact resistance and damage tolerance of composite structures are introduced. Internal non-visible or barely visible impact damage (NVID, BVID) can provoke a significant strength and stability reduction in monolithic composite structures as well as in composite sandwich structures. Therefore, methodologies have been developed to reliably simulate the dynamic response and to predict the impact damage size that develops during low-velocity impact (LVI) events. Additionally, methods for the prediction of the compression-after-impact (CAI) strength are presented. Special attention is given to the impact assessment methodologies, which have been implemented in the DLR in-house tool CODAC. Simulation results of CODAC are presented and compared to experimental results.

Keywords

Sandwich Structure Face Sheet Impact Damage Fiber Breakage Stiffness Reduction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. 1.
    Hashin, Z.: Failure criteria for unidirectional fibre composites. J. Appl. Mech. 47, 329–334 (1980)CrossRefGoogle Scholar
  2. 2.
    Puck, A., Schürmann, H.: Failure analysis of FRP laminates by means of physically based phenomenological models. Compos. Sci. Technol. 58, 1045–1067 (1998)CrossRefGoogle Scholar
  3. 3.
    Choi, H.Y., Chang, F.K.: A model for predicting damage in graphite/epoxy laminated composites resulting from low-velocity impact. J. Compos. Mater. 14, 2134–2168 (1992)CrossRefGoogle Scholar
  4. 4.
    Chai, Y.: A finite element method for predicting impact damage in composite stiffened-panels. Master degree dissertation, North-Western Polytechnical University (NPU) (1996)Google Scholar
  5. 5.
    Kärger, L., Baaran, J., Gunnion, A., Thomson, R.: Evaluation of impact assessment methodologies. Part I: applied methods. Compos. B 40, 65–70 (2009)CrossRefGoogle Scholar
  6. 6.
    Besant, T., Davies, G.A.O., Hitchings, D.: Finite element modelling of low velocity impact of composite sandwich panels. Compos. A 32, 1189–1196 (2001)CrossRefGoogle Scholar
  7. 7.
    Kintscher, M., Kärger, L., Wetzel, A., Hartung, D.: Stiffness and failure behaviour of folded sandwich cores under combined transverse shear and compression. Compos. A 38, 1288–1295 (2007)CrossRefGoogle Scholar
  8. 8.
    Kärger, L.: Effiziente Simulation von Schlagschädigungen in Faserverbund-Sandwichstrukturen. Dissertation, TU Braunschweig (2007)Google Scholar
  9. 9.
    Kärger, L., Baaran, J., Teßmer, J.: Efficient simulation of low-velocity impacts on composite sandwich panels. Comput. Struct. 86, 988–996 (2008)CrossRefGoogle Scholar
  10. 10.
    Wetzel, A.: Effiziente Ermittlung der Restfestigkeit schlaggeschädigter Sandwichstrukturen aus Faserverbundwerkstoff. Dissertation, TU Braunschweig (2008)Google Scholar
  11. 11.
    Abrate, S.: Impact on Composite Structures. Cambridge University Press, Cambridge (1998) Google Scholar
  12. 12.
    Baaran, J., Kärger, L., Wetzel, A.: Efficient prediction of composite damage resistance and damage tolerance. J. Aerosp. Eng. 222(1), 179–188 (2008)Google Scholar
  13. 13.
    Rolfes, R., Rohwer, K.: Improved transverse shear stresses in composite finite elements based on first order shear deformation theory. Int. J. Numer. Methods Eng. 40, 51–60 (1997)CrossRefGoogle Scholar
  14. 14.
    Kärger, L., Baaran, J., Gunnion, A., Thomson, R.: Evaluation of impact assessment methodologies. part ii: experimental validation. Compos. B 40, 71–76 (2009)CrossRefGoogle Scholar
  15. 15.
    Kärger, L., Wetzel, A., Rolfes, R., Rohwer, K.: A three-layered sandwich element with improved transverse shear stiffness and stresses based on FSDT. Comput. Struct. 84, 843–854 (2006)CrossRefGoogle Scholar
  16. 16.
    Wetzel, A., Kärger, L., Rolfes, R., Rohwer, K.: Evaluation of two finite element formulations for a rapid 3D stress analysis of sandwich structures. Comput. Struct. 83, 1537–1545 (2005) CrossRefGoogle Scholar
  17. 17.
    Chai, H., Babcock, C.D.: Two-dimensional modeling of compressive failure in delaminated laminates. J. Compos. Mater. 19, 67–99 (1984)CrossRefGoogle Scholar
  18. 18.
    Tang, X., Shen, Z., Chen, P., Gädke, M.: Methodology for residual strength of damaged laminated composites. AIAA-97-1220 (1997)Google Scholar
  19. 19.
    Tsang, P.H.W., Lagace, P.A.: Failure mechanisms of impact-damaged sandwich panels under uniaxial compression. In: Proceedings of the AIAA/ASME/ASCE/AHS/ASC 35nd structures, structural dynamics, and materials conference, hilton head, pp. 745–754 (1994)Google Scholar
  20. 20.
    Wetzel, A., Baaran, J.: A semi-analytical methodology for the residual strength prediction of damaged sandwich structures. In: Proceedings of the ECCM 13, Stockholm, Sweden. 2–5 June 2008Google Scholar
  21. 21.
    Olsson, R.: Methodology for predicting the residual strength of impacted sandwich panels. Report FFA TN 1997-09, The Aeronautical Research Institute of Sweden (1997)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Institute of Composite Structures and Adaptive SystemsGerman Aerospace Center (DLR e.V.)BraunschweigGermany

Personalised recommendations