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Studying buckling behavior of large shell structures through full-scale test articles can be complex and expensive. Therefore, reduced-scale structures are often preferred for investigating bucklin...

The functional reconstitution technique is used for the first time to theoretically and a priori assess the numerical performance of Reissner’s Mixed Variational Theorem in the case of linear quadr...

A new higher-order zig-zag theory is proposed for the free and forced vibration analysis of laminated composite and sandwich beams with different thickness at each ply. In-plane displacements in th...

It will be shown that the generic integral equation for nondestructive determination of the buckling loads obtained previously (Baruch, M., Integral Equations for Nondestructive Determination of Buckling Loads for Elastic Bars and Plates, Israel Journal of Technology, Vol. 11, No. 1-2, 1973, pp. 1-8) includes the influence of the transverse shear strains on the buckling load. This can not be said for the integral equations obtained by differentiation of the generic integral equation.

The Raasch challenge problem of a curved strip with a tip in-plane shear load is examined in an attempt to better understand how certain shell element features affect its solution. Various shell element formulations are used in the assessment in an attempt to de® neany inherent pathological problems of the shell ® niteelements or the

KIRCHHOFF’S theory [1] and the first-order shear deformation theory (FSDT) [2] of plates in bending are simple theories and continuously used to obtain design information. Within the classical small deformation theory of elasticity, the problem consists of determining three displacements, u, v, and w, that satisfy three equilibrium equations in the interior of the plate and three specified surface conditions. FSDT is a sixth-order theory with a provision to satisfy three edge conditions and maintains, unlike in Kirchhoff’s theory, independent linear thicknesswise distribution of tangential displacement even if the lateral deflection, w, is zero along a supported edge. However, each of the in-plane distributions of the transverse shear stresses that are of a lower order is expressed as a sum of higher-order displacement terms. Kirchhoff’s assumption of zero transverse shear strains is, however, not a limitation of the theory as a first approximation to the exact 3-D solution.

Developpement d'une theorie des coques statiques geometriquement non lineaires, qui inclut des deformations de cisaillement transversales paraboliques. On utilise des elements rectangulaires courbes a 28 et a 36 degres de liberte. On donne des solutions lineaires pour une plaque stratifiee plate, pour une enceinte cylindrique stratifiee isotrope sous pression. Comparaison avec les resultats classiques de Love. Influence de l'epaisseur

Analysis methods and joint design details h ave b een developed for adhesively bonded aluminum h oneycomb i n aircraft primary structure. Joint d esign d etails, which were tested f or strength, durability and e nvironmental resistance, p rovide

La premiere partie a presente la solution de l'analyse de vibration et d'amortissement d'une coque cylindrique generale a plusieurs couches, composee d'un nombre arbitraire de couches viscoelastiques et elastiques d'un materiau orthotrope, avec des conditions de simple supportage aux extremites. La solution a ete programmee sur ordinateur IBM 360 pour l'evaluation des frequences de resonance et les facteurs de perte associes pour toutes les familles de modes ayant les vibrations axisymetriques et non axisymetriques de l'enveloppe multicouches. Le cas d'enveloppes a 3, 5, et 7 couches alternativement elastiques et viscoelastiques a ete examine

Constant thickness elastic conical shells subject to lateral loads, deriving asymptotic solution

Finite difference method stability analysis of deformed eccentrically stiffened shells of revolution, accounting for finite prebuckling rotations

Macroscopic viscoelastic properties of fiber reinforced materials analyzed on basis of composite cylinder assemblage model and correspondence principle

The governing equations on bending of multilayered orthotropic (both core and facings) sandwich plates are developed through the use of variational methods. The plate is assumed to consist of j facings and (j — 1) cores, having different thicknesses and possessing different orthotropic elastic properties. In-plane stresses in the cores are neglected as is the variation of stresses across the facings. The developed theory is an extension of that given in Ref. 7. Nomenclature a, b = length of rectangular plate in the x- and y-directions, respectively Dxz, Dyz — transverse shear rigidities of plate DXj Dy = bending rigidities of plate in x- and ^-directions, respectively DXy = twisting rigidity of plate Eix, Eiy = Young's moduli of the ith facing in the x- and ^/-directions, respectively Gixz, Giyz = shear moduli of the ith core hi = thickness of the ith core Lr(r = 1-8) = Lagrange multipliers MX, My, MXy = stress couples per unit length of plate NX, Ny, NXy = normal and in-plane shear stress resultants per unit length of plate pz = load function per unit area applied normal to the plate QX) Qy = transverse shear forces per unit length of plate

References ^owinski, J. L., "Nonlinear Vibrations of Elastic Circular Plates Exhibiting Rectilinear Orthotropy," Zeitschrift fuer Angewandte Mathematik UndPhysik, Vol. 14, 1963, pp. 113-124. Yamaki, N., "Influence of Large Amplitude on Flexural Vibrations of Elastic Plates," Zeitschrift fuer Angewandte Mathematik UndMecianik, Vol. 41, 1961, pp. 501-510. Wah, T., "Vibration of Circular Plates at Large Amplitudes," Journal of Engineering Mechanics Division, ASCE, Vol. 89, 1963, pp. 1-15. Sathyamoorthy, M., "Nonlinear Vibrations of Plates—A Review," The Shock and Vibration Digest, Vol. 15, June 1983, pp. 316. Wu, C. I. and Vinson, J. R., "On the Nonlinear Oscillations of Plates Composed of Composite Materials," Journal of Composite Materials, Vol. 3, 1969, pp. 548-561. Sathyamoorthy, M., "Transverse Shear and Rotatory Inertia Effects on Nonlinear Vibration of Orthotropic Circular Plates," Computers and Structures, Vol. 14, 1981, pp. 129-134.