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Theory of Wrinkling in SandwichConstruction

Published online by Cambridge University Press:  28 July 2016

Syed Yusuff
Syed Yusuff*
Affiliation:
The Bristol Aeroplane Co. Ltd., Filton
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Summary

In this paper a theory of wrinkling in Sandwich Construction is presented in two parts. In the first part, the thickness of the core is regarded as finite. The wrinkling stress is given by a simple square root formula consisting of the Young's moduli of the materials and the ratio of the thickness of the face and core. In the second part of the theory the same procedure is followed, with the main difference that shearing stresses in the core are also considered, and the analysis is extended to the case where the face is supported by a sufficiently thick or a semi-infinite medium. The result for the wrinkling stress is a cubic root formula which consists of the moduli of the materials but indirectly depends upon the geometry of the structure; this formula is valid only if the ratio of the thickness of the core and the face is greater than or at least equal to the ratio of the width of the marginal zone of distortions in the core, and the thickness of the face. The width of the zone is also useful as the criterion which discriminates between the two cases of buckling as envisaged in this paper. The theory is compared with the previous works, and also with the test results already available. The selection of the experimental data comprises steel, aluminium alloy and Papreg (laminated paper plastic) as the face; and onazote, cellular cellulose acetate, granulated cork, sponge rubber and expanded formvar as the core materials over a wide range of core-face thickness ratio. The agreement between the theory and the tests is satisfactory.

Type
Research Article
Information
The Aeronautical Journal , Volume 59 , Issue 529 , January 1955 , pp. 30 - 36
Copyright
Copyright © Royal Aeronautical Society 1955

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References

1. Gough, Elam and Bruyne, De (1940). The Instability of Thin Sheet by a Supporting Medium. Journal of the Royal Aeronautical Society, Vol. XLIV, No. 349, p. 12, January 1940.Google Scholar
2. Williams, D., Leggett, D. M. A. and Hopkins, H. G. (1941). Flat Sandwich Panels Under Compressive End Loads. R. & M. No. 1987, June 1941.Google Scholar
3. Hoff, N. J. and Mautner, S. E. (1945). The Buckling of Sandwich Type Panels. Journal of the Institute of Aeronautical Sciences, Vol. 12, No. 3, p. 285, July 1945.Google Scholar
4. Cox, H. L. (1945). Sandwich Construction and Core Materials, Part III. Instability of Sandwich Strut and Beams. A.R.C. Paper No. 9226-Strut 974, December 1945.Google Scholar
5. Barwell, F. T. and Riddell, J. R. (1946). The Wrinkling of Sandwich Struts. A.R.C. Paper No. 9067-Strut 946 (revised), June 1946.Google Scholar
6. Williams, D. (1947). Sandwich Construction—A Practical Approach for the Use of Designers. R.A.E. Report No. Structure 2, April 1947.Google Scholar
7. Boller, Kenneth H. (1947). Preliminary Report on the Strength of Flat Sandwich Plates in Edge Compression. USDA–FPL. Report No. 1561, 1947.Google Scholar
8. Norris, C. B., Erickson, W. S., March, H. W., Smith, C. B. and Boller, K. H. (1949). Wrinkling of the Facings of Sandwich Construction Subjected to the Edgwise Compression. USDA–FPL. Report No. 1810, November 1949.Google Scholar
9. Kármán, Th. von, and Biot, Maurice A. (1940). Mathematical Methods in Engineering, 1st Edition, p. 305. McGraw-Hill, New York, 1940.Google Scholar