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Stainless-steel wine tanks buckled at the Wente Brothers Winery in the Livermore, Calif., earthquake of Jan. 24,1980. The buckled tanks were all completely filled.(Photographs courtesy of J. Skogh.)
From:
David Bushnell, “Buckling of shells - Pitfall for designers, AIAA Journal, Vol. 19, No. 9, September 1981, pp 1183-1226
INTRODUCTION: In order to produce efficient, reliable designs & to avoid unexpected catastrophic failure of structures of which thin shells are important components, the engineer must understand the physics of shell buckling. The objective of this survey is to convey to the reader a “feel” for shell buckling, whether it be due to nonlinear collapse, bifurcation buckling, or a combination of these modes. This intuitive understanding of instability is communicated by a large number of examples involving practical shell structures which may be stiffened, segmented, or branched & which have complex wall constructions. With such intuitive knowledge the engineer will have an improved ability to foresee situations in which buckling might occur & to modify a design to avoid it. He or she will be able to set up more appropriate models for tests & analytical predictions. The emphasis here is not on the development of equations for the prediction of instability. For such material the reader is referred to the book by Brush & Almroth. Emphasis is given here to nonlinear behavior caused by a combination of large deflections & plasticity. Also illustrated are stress redistribution effects, stiffener & load-path eccentricity effects, local v. general instability, imperfection sensitivity, & modal interaction in optimized structures. Scattered throughout the text are tips on modeling for computerized analysis. The survey is divided into nine major sections describing: 1) several examples of catastrophic failure of expensive shell structures; 2) the basics of buckling behavior; 3) “classical” buckling & imperfection sensitivity; 4) nonlinear collapse & the appropriateness of linear bifurcation buckling analyses for general shells; 5) bifurcation buckling with significant nonlinear pre-buckling behavior; 6) effects of boundary conditions, load eccentricity, transverse shear deformation, & stable post-buckling behavior; 7) optimization of buckling-critical structures with consequent modal interaction; 8) a suggested design method for axially compressed cylinders with stiffeners, internal pressure, or other special characteristics; & 9) two examples in which sophisticated buckling analyses are required in order to derive improved designs. The paper focuses on static buckling problems
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