Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-28T10:31:02.148Z Has data issue: false hasContentIssue false

A Bending Theory for Multi-layer Anisotropic Conical Shells

Published online by Cambridge University Press:  07 June 2016

Boen-Dar Liaw*
Affiliation:
Brown Engineering Company, Huntsville, Alabama
Get access

Summary

The governing equations for bending of truncated conical shells with multi-layer anisotropic construction are developed by a variational method. The shell is considered to consist of an arbitrary number of alternating soft and hard layers. It is assumed further that the n hard membrane layers are isotropic and may possess different elastic properties, while the (n-1) soft core layers are orthotropic in general and may take transverse shear only. The variations of stresses across the membranes are neglected, as are the surface-parallel stresses in the cores. These assumptions are consistent with those usually employed in single-core sandwich shells. The energy functional is formulated with the stresses considered as independent variables. The stresses are also dependent variables defined in the set of two curvilinear co-ordinates defining the surface of the shell. The stress resultants are introduced as constraint conditions utilising Lagrange multipliers. Successful definition of an elastic neutral surface ensures the uniqueness of shell constants and the equations obtained may be in a form comparable to that of classical shell theory. The system of equations is reduced to a form where Galerkin’s method can be applied directly.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1969

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. Habip, L. M. A survey of modern developments in the analysis of sandwich structures. Applied Mechanics Reviews, Vol. 18, No. 2, 1965.Google Scholar
2. Reissner, E. Small bending and stretching of sandwich-type shells. NACA TN 1832, 1949.Google Scholar
3. Wang, C. T. Principle and application of complementary energy methods for thin homogeneous and sandwich plates and shells with finite deflections. NACA TN 2620, 1952.Google Scholar
4. Rutecki, J. Equations of a conical sandwich shell ribbed inside and with a weak core. Rozprawy Inz., Vol. 8, pp. 781801; AMR 15, 1962, Rev. 6969.Google Scholar
5. Liaw, B. D. Theory of bending of multilayer sandwich plates. PhD Dissertation, Oklahoma State University, Stillwater, Oklahoma, 1965.Google Scholar
6. Wong, J. P. Stability of multilayer sandwich plates. PhD Dissertation, Oklahoma State University, Stillwater, Oklahoma, 1966.Google Scholar
7. Kao, J. S. Axisymmetrical deformation of multilayer circular sandwich cylindrical shells. Journal of the Franklin Institute, Vol. 282, No. 1, 1966.CrossRefGoogle Scholar
8. Naghdi, P. M. On the Theory of thin elastic shells. Quarterly of Applied Mathematics, Vol. 14, No. 4, pp 369380, 1957.CrossRefGoogle Scholar
9. Hu, W. C. L. Free vibrations of conical shells. NASA TN D-2666, 1965.Google Scholar