| Autor: |
N. J. HOFF, W. E. JAHSMAN, W. NACHBAR |
| Rok vydání: |
1959 |
| Předmět: |
|
| Zdroj: |
Journal of the Aerospace Sciences. 26:663-669 |
| ISSN: |
1936-9999 |
| DOI: |
10.2514/8.8243 |
| Popis: |
A long, thin-walled cylindrical shell is loaded by a uniform external pressure. Equations are developed for the time behavior of the shape of the cross section under the following conditions: (a) the shell material exhibits only secondary (steady) creep deformations expressible by a power creep law; (b) the initial and subsequent mode shape of the deviations from circularity of any cross section is two-lobed; and (c) the shell construction is of the sandwich type, with concentric cylindrical membranes taking normal stresses and an annular core supporting shear without deformation. Explicit solutions are obtained for the particular case of the cubic creep law. I t is shown tha t the nondimensional amplitude of the cross-sectional mode shape (briefly, shape factor) will become infinite in a finite time. Curves of shape factor versus time and of collapse time versus initial value of the shape factor are presented. Also given are an explicit expression for and a curve of the expected variation in collapse time owing to uncontrollable deviations from a nominal initial value of the shape factor. I t is shown that the expected variation is small if the nominal initial shape factor value is sufficiently large. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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