Effects of Anisotropy in Axisymmetric Cylindrical Shells

1967 ◽  
Vol 34 (3) ◽  
pp. 659-666 ◽  
Author(s):  
S. T. Gulati ◽  
F. Essenburg
Keyword(s):  
Cylindrical Shell ◽  
Shear Deformation ◽  
Transverse Shear ◽  
Shell Theory ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Practical Importance ◽  
Transverse Shear Deformation ◽  
Circumferential Displacement

The solution of the problem of the generally anisotropic axisymmetric circular cylindrical shell is obtained employing a recent shell theory given by Naghdi. The practical importance of the presence of the circumferential displacement components and the twisting couple arising due to the presence of anisotropy, as well as the significance of the inclusion of the coupled effects of transverse shear deformation and anisotropy, are illustrated by a specific example.

Free Asymmetric Vibrations of Composite Full Circular Cylindrical Shells Stiffened by a Bonded Central Shell Segment

2004 ◽  
Author(s):  
U. Yuceoglu ◽  
V. O¨zerciyes
Keyword(s):  
Cylindrical Shell ◽  
Shell Theory ◽  
Natural Frequencies ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Adhesive Layer ◽  
Shear Stresses ◽  
First Order ◽  
Stress Resultant ◽  
Circular Cylindrical Shells

This study is concerned with the “Free Asymmetric Vibrations of Composite Full Circular Cylindrical Shells Stiffened by a Bonded Central Shell Segment.” The base shell is made of an orthotropic “full” circular cylindrical shell reinforced and/or stiffened by an adhesively bonded dissimilar, orthotropic “full” circular cylindrical shell segment. The stiffening shell segment is located at the mid-center of the composite system. The theoretical analysis is based on the “Timoshenko-Mindlin-(and Reissner) Shell Theory” which is a “First Order Shear Deformation Shell Theory (FSDST).” Thus, in both “base (or lower) shell” and in the “upper shell” segment, the transverse shear deformations and the extensional, translational and the rotary moments of inertia are taken into account in the formulation. In the very thin and linearly elastic adhesive layer, the transverse normal and shear stresses are accounted for. The sets of the dynamic equations, stress-resultant-displacement equations for both shells and the in-between adhesive layer are combined and manipulated and are finally reduced into a ”Governing System of the First Order Ordinary Differential Equations” in the “state-vector” form. This system is integrated by the “Modified Transfer Matrix Method (with Chebyshev Polynomials).” Some asymmetric mode shapes and the corresponding natural frequencies showing the effect of the “hard” and the “soft” adhesive cases are presented. Also, the parametric study of the “overlap length” (or the bonded joint length) on the natural frequencies in several modes is considered and plotted.

On a Laminated Orthotropic Shell Theory Including Transverse Shear Deformation

1972 ◽  
Vol 39 (4) ◽  
pp. 1091-1097 ◽  
Author(s):  
S. B. Dong ◽  
F. K. W. Tso
Keyword(s):  
Shear Deformation ◽  
Transverse Shear ◽  
Shell Theory ◽  
Orthotropic Shell ◽  
Plane Waves ◽  
Present Theory ◽  
Transverse Shear Deformation ◽  
Correction Factors ◽  
Natural Oscillations ◽  
Orthotropic Shells

A constitutive relation for laminated orthotropic shells which includes transverse shear deformation is presented. This relation involves composite correction factors k112, k222 which are determined from an analysis of plane waves in a plate with the same layered construction. The range of applicability of the present theory and the quantitative effect of transverse shear deformation are evinced in a problem concerned with the natural oscillations of a three-layered freely supported cylinder.

Creep Buckling and Post-Buckling Analyses of a Viscoelastic FGM Cylindrical Shell with Initial Deflection Subjected to a Uniform In-Plane Load

2012 ◽  
Vol 28 (2) ◽  
pp. 391-399 ◽  
Author(s):  
H.-L. Dai ◽  
H.-Y. Zheng
Keyword(s):  
Cylindrical Shell ◽  
Shear Deformation ◽  
Transverse Shear ◽  
Volume Fraction ◽  
Superposition Principle ◽  
Functionally Graded ◽  
Initial Deflection ◽  
Transverse Shear Deformation ◽  
Creep Buckling ◽  
Post Buckling

AbstractIn this paper, based on the viscoelastic theory, the creep buckling and post-buckling behaviors of a viscoelastic functionally graded material (FGM) cylindrical shell with initial deflection subjected to a uniform in-plane load are investigated. The material properties of the viscoelastic FGM cylindrical shell are assumed to vary through the structural thickness according to a power law distribution of the volume fraction of constituent materials and Poisson's ratio is assumed as a constant. Considering the transverse shear deformation and geometric nonlinearity, the constitutive relation of the viscoelastic FGM cylindrical shell is established. By means of the Newton-Newmark method and the Boltzmann superposition principle, the problem for the creep buckling and post-buckling of the FGM cylindrical shell is solved. The numerical results reveal that the transverse shear deformation, volume fraction and geometric parameters have significant effects on the creep buckling and post-buckling of the viscoelastic FGM cylindrical shell.

scholarly journals Critical Frequencies of Composite Cylindrical Shells

2020 ◽  
Vol 25 (1) ◽  
pp. 79-87
Author(s):  
K. Renji ◽  
S. Josephine Kelvina Florence
Keyword(s):  
Cylindrical Shell ◽  
Shear Deformation ◽  
Transverse Shear ◽  
Critical Frequency ◽  
Composite Panel ◽  
Transverse Shear Deformation ◽  
Composite Cylindrical Shell ◽  
Composite Cylinder ◽  
Bending Waves ◽  
Bending Wave

The sound radiation characteristics of a structure depend on its critical frequency. The expression for theoretically estimating the critical frequency of a composite cylindrical shell has not yet been reported. Thus, the practice is to use the expression for the composite panel for determining the critical frequency of a composite shell. In this work, critical frequencies of composite shells are investigated. As the critical frequency depends on the speed of the bending wave, an expression for the speed of the bending wave is first derived. It is seen that the curvature causes an increase in the speed of the bending wave and the orthotropic nature of the cylinder reduces the speed. An expression for the critical frequency of a composite cylindrical shell is then derived. The curvature causes a reduction in the critical frequency and the influence is significant in acoustically thick cylinders. Hence, the critical frequencies of such cylinders cannot be determined by using the expression for the panels. Effects of transverse shear deformation on the speed of the bending wave as well as the critical frequency are then investigated. Transverse shear deformation causes both reduction in the speed of the bending wave and an increase in the critical frequency. The orthotropic nature of the cylindrical shell increases the critical frequency further. The critical frequency of a typical composite cylinder is determined through a numerical simulation and the results are in agreement with the results obtained using the expressions derived. The critical frequency of a typical composite cylinder obtained through an experiment is presented. With this work, expressions for theoretically estimating the speeds of the bending waves and critical frequencies are derived for a composite cylindrical shell considering transverse shear deformation.

Transient Solutions of a Longitudinally Impacted Conical Shell

1971 ◽  
Vol 38 (2) ◽  
pp. 545-547 ◽  
Author(s):  
R. W. Mortimer ◽  
A. Blum
Keyword(s):  
Shear Deformation ◽  
Transverse Shear ◽  
Conical Shell ◽  
Method Of Characteristics ◽  
Shell Theory ◽  
Experimental Results ◽  
Transverse Shear Deformation ◽  
Longitudinal Impact ◽  
Governing Equations ◽  
Transient Solutions

A thin conical shell theory, which includes the effects of transverse and rotary inertias and transverse shear deformation, is used to analyze the response of a conical shell to longitudinal impact. The governing equations of this theory are solved by the method of characteristics and the results are compared to published experimental results.

Axisymmetric Free Vibrations of Conical Shells

1964 ◽  
Vol 31 (3) ◽  
pp. 458-466 ◽  
Author(s):  
Hyman Garnet ◽  
Joseph Kempner
Keyword(s):  
Shear Deformation ◽  
Transverse Shear ◽  
Thin Shell ◽  
Shell Theory ◽  
Free Vibrations ◽  
Transverse Shear Deformation ◽  
Rotatory Inertia ◽  
Conical Shells ◽  
Thin Shell Theory ◽  
Thickness Parameter

The lowest axisymmetric modes of vibration of truncated conical shells are studied by means of a Rayleigh-Ritz procedure. Transverse shear deformation and rotatory inertia effects are accounted for, and the results are compared with those predicted by the classical thin-shell theory. Additionally, the results are compared when either of these theories is formulated in two ways: First, in the manner of Love’s first approximation in the classical thin-shell theory, and then by including the influence of the change of the element of arc length through the thickness. It was found that the Love and the more complex formulation yielded results which differed negligibly in either theory. The results predicted by the shear deformation-rotatory inertia theory differed significantly from those predicted by the classical thin-shell theory within a range of parameters which characterize short thick cones. These differences resulted principally from the influence of the transverse shear deformation. It was also found that within this short-cone range an increase in the shell thickness parameter was accompanied by an increase in the natural frequency. Moreover, the increase in frequency with increasing thickness parameter became less severe as the length-to-mean radius ratio was increased. For the longer cones, the frequency was virtually independent of the thickness.

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