Accession Number : AD0422297

Title :   TESTS OF STIFFENED AND UNSTIFFENED MACHINED SPHERICAL SHELLS UNDER EXTERNAL HYDROSTATIC PRESSURE

Corporate Author : DAVID TAYLOR MODEL BASIN WASHINGTON DC

Personal Author(s) : Krenzke, Martin A. ; Kiernan, Thomas J.

PDF Url : AD0422297

Report Date : AUG 1963

Pagination or Media Count : 81

Abstract : Four series of structural models, consisting of 102 small machined spherical shells, were tested to study the effect of unsupported shell length on both their elastic and inelastic buckling strength. The collapse pressure of the complete spheres was adequately calculated using the empirical equation earlier developed at the model basin. Whereas previous experiments on spherical shells with clamped edges recorded in the literature show a complete lack of repeatability, the results of the present models follow a definite pattern. These tests demonstrate that the unsupported shell length must be relatively short to provide an increase in strength of a spherical segment over that of a complete sphere. They also demonstrate that a small clamped spherical segment may be weaker than a longer clamped segment. The experimental collapse strength of the stiffened shells was in no case as great as wnuld be expected for a machined unstiffened shell of the same weight. Since these were rather exploratory tests, however, they do not demonstrate that effective stiffening systems cannot be developed.

Descriptors :   *SPHERES, *MODEL TESTS, *SUBMARINE HULLS, *HEMISPHERICAL SHELLS, STRESSES, THICKNESS, REINFORCING MATERIALS, HYDROSTATIC PRESSURE, PRESSURE VESSELS, MACHINING, PHYSICAL PROPERTIES, ELASTIC PROPERTIES

Subject Categories : Submarine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE