Analytical Prediction of Indentation and Low-Velocity Impact Responses of Fully Backed Composite Sandwich Plates

Document Type: Research Paper

Authors

1 Centre of Excellence for Research in Advanced Materials and Structures, Faculty of Mechanical Engineering, K.N. Toosi University of Technology

2 Centre of Excellence for Research in Advanced Materials and Structures, Faculty of Mechanical Engineering, K.N. Toosi University of Technology--- Faculty of Engineering, Kingston University, London

Abstract

In this paper, static indentation and low velocity impact responses of a fully backed composite sandwich plate subjected to a rigid flat-ended cylindrical indenter/impactor are analytically investigated. The analysis is nonlinear due to nonlinear strain-displacement relation. In contrast to the existed analytical models for the indentation of composite sandwich plates, the stacking sequence of the face sheets can be completely arbitrary in the present model. Furthermore, the effects of the initial in-plane normal and shear forces on the edges of the sandwich plate are also considered. Based on these modifications, an improved contact law (contact force – indentation relation) is derived. The low velocity impact analysis of the problem is performed using a discrete system of spring-mass-dashpot model. The characteristics of the equivalent spring and dashpot are identified from the derived contact law and by incorporating the effect of the dynamic material properties of the sandwich plate. Analytical predictions of the load-indentation response as well as the impact force history are compared well with the experimental results in the literature. The effects of various parameters on both indentation and impact responses of the sandwich plates are qualitatively and quantitatively investigated.

Keywords


[1] Abrate S., 1998, Impact on Composite Structures, Cambridge University Press, Cambridge.

[2] Khalili M.R., 1992, Analysis of the dynamic response of large orthotropic elastic plates to transverse impact and its application to fiber reinforced plates, PhD thesis , Indian Institute of Technology , Delhi.
[3] Mittal R.K., Khalili M.R., 1994, Analysis of impact of a moving body on an orthotropic elastic plate, The American Institute of Aeronautics and Astronautics 32(4):850-856.
[4] Wu H-YT., Chung F-K., 1989, Transient dynamic analysis of laminated composite plates subjected to transverse impact, Computers & Structures 31:453-466.
[5] Gong S.W., Toh S.L., Shim P.W., 1994, The elastic response of orthotropic laminated cylindrical shells to low-velocity impact, Composites Engineering 4(2):247-266.

[6] Williamson J.E., Lagace P.A., 1993, Response mechanism in the impact of graphite/epoxy honeycomb sandwich panels, Proceeding of the Eighth ASC Technical Conference, Cleveland, Ohio.

[7] Herup E.J., Palazotto A.N., 1997, Low-velocity impact damage initiation in graphite/epoxy/nomex honeycomb-sandwich plates, Composites Science and Technology 57:1581-1598.

[8] Turk M.H., Hoo Fatt M.S., 1999, Localized damage response of composite sandwich plates, Composites: Part B 30: 157-165.

[9] Hoo Fatt M.S., Park K.S., 2001, Dynamic models for low-velocity impact damage of composite sandwich panels- part a deformation, Composite Structures 52:335-351.

[10] Olsson R., McManus H.L., 1996, Improved theory for contact indentation of sandwich panels, The American Institute of Aeronautics and Astronautics 34:1238-1244.

[11] Anderson T., Madenci E., 2000, Graphite/epoxy foam sandwich panels under quasi-static indentation, Engineering Fracture Mechanics 67:329-344.

[12] Gibson L.J., Ashby M.F., 1997, Cellular Solids Structures and Properties, Cambridge University Press, Cambridge.

[13] Malekzadeh K., Khalili M.R., Mittal R.K., 2006, Response of in-plane linearly prestressed composite sandwich panels with transversely flexible core to low-velocity impact, Journal of Sandwich Structures and Materials 8:157-181.

[14] Hosseini M., Khalili S.M.R., Malekzadeh Fard K., 2011, Indentation analysis of in-plane prestressed composite sandwich plates: an improved contact law, Proceedings of the Eighth International Conference on Composite Science and Technology, Kuala Lumpur, Malaysia.

[15] Goldsmith W., Sackman J.L., 1991, An experimental study of energy absorption in impact on sandwich plates, The International Journal of Impact Engineering 12(2):241-262.