Optimal design of columns.
Optimization procedure to minimize volume in design of columns of given cross sectional style and equal buckling load
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Optimization procedure to minimize volume in design of columns of given cross sectional style and equal buckling load
Gravity-loades axial-compression test fixture is operated by raising lower platen and specimen against weighted upper platen. Wheel turns nut on threaded rod to move lower platen up or down. Limiting rods prevent further upward movement if sample buckles.
This paper discusses an investigation into the thermal buckling of symmetrically laminated composite plates. In this study thermal buckling is investigated for laminates under two different simple support conditions, fixed and sliding. These laminates are subjected to the conditions of a uniform temperature change, and a temperature change varying linearly along the length of the plate. The effects of the principal material axes not being aligned with the edges of the plate are also investigated. The buckling response is studied using variational methods, specifically the Trefftz criterion. A Rayleigh-Ritz formulation is used to obtain numerical results from the formulations for the prebuckling response and the buckling response.
Three series of experiments were performed to investigate the nature of the buckling phenomenon. They were: a) influence of an increasing dimple on the buckling load of a cylinder; b) investigation of the strain distribution on one cylinder, after one or more waves were imposed on it; c) measurements of lateral deflections at buckling. The results of such experiments give some support to the idea of a buckling model, which can be of eventual interest to the thin wall cylinder and cone buckling problem, where a non-linear system (the buckled band) is considered in series with a linear system (the unbuckled portion of the cylinder, plus the testing-machine )
Supersonic effects of thermal stress and buckling on flutter of flat panels
Lower bounds of buckling pressure of spherical shells
Large deflection theory for determining the buckling pressure of spherical shells
Testing machine effect on buckling load of electroformed cylindrical shells under axial compression
Nonconservative loading on linear two-degree of freedom elastic system, discussing damping effects on equilibrium stability
The natural vibration frequencies of orthotropic and anisotropic, simply supported right circular cylinders are predicted using a theory which takes into account higher-order transverse shear deformation effects. A comparison between results based on first-order transverse shear deformation theory and the higher-order theory indicates that an additional allowance for transverse shear deformation has a negligible effect on the predicted natural vibration frequencies associated with long wavelengths, but significantly reduces the natural vibration frequencies associated with short wavelengths. Results of a parametric study of ply orientation for two classes of laminates indicates that while stacking sequence affects natural vibration frequencies, cylinder geometry and mode shape are more important in accurately predicting transverse shear deformation effects. Transverse shearing effects are less important in predicting natural vibration frequencies associated with long wavelength than in predicting axial compressive buckling loads.
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Hydrostatic buckling pressure calculations for spherical shells
End slope effect on buckling stress of seamless cylindrical shells
Testing machine influence on buckling of cylindrical shells under axial compression
The buckling and failure characteristics of unstiffened, blade stiffened, and hat stiffened graphite-polyimide shear panels are described. The picture frame shear test is used to obtain shear stress-strain data at room temperature and at 316 deg C. The experimental results are compared with a linear buckling analysis, and the specimen failure modes are described. The effect of the 316 deg C test temperature on panel behavior are discussed.
Imperfection survey data on cylindrical shells before and during axial compression loading up to buckling load
Simple, inexpensive, one-shot load device uses thin-walled soft-metal tube to absorb kinetic energy by controlled buckling.
The impetus of composite mechanics on composite test methods and/or on interpreting test results is described by using examples from composite micromechanics, composite macromechanics and laminate theory. The specific examples included contributions such as criteria for selecting resin matrices for improved composite strength, the 10 deg off-axis tensile test, criteria for configuring hybrids and superhybrids for improved impact resistance and the reduced bending rigidities concept for buckling and vibration analyses.