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Finite Elements for Curved Sandwich Beams

Published online by Cambridge University Press:  07 June 2016

P J Holt
Affiliation:
Department of Aeronautical Engineering, University of Bristol
J P H Webber
Affiliation:
Department of Aeronautical Engineering, University of Bristol
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Summary

The formulation of curved finite elements to represent a two-dimensional circular sandwich ring with honeycomb core and laminated faces is investigated. Assumed stress hybrid and equilibrium methods are found to be easier to employ in this case than the displacement approach. Using these methods, an element stiffness matrix is developed. The approximations of membrane faces and an infinite core normal stiffness are then used to develop simpler elements. Test cases show that these assumptions may become invalid, but that they are adequate for most practical cases where the core thickness to radius ratio and the face thickness to core thickness ratio are both low.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1977

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References

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