Bifurcation Buckling of Circular Cylindrical Shells Subjected to Axial Compression During Creep Deformation

1993 ◽  
Vol 115 (3) ◽  
pp. 268-274 ◽  
Author(s):  
N. Miyazaki ◽  
S. Hagihara

In the present work, analytical and experimental investigations were performed on creep buckling. Special attention was focussed on bifurcation behavior during creep deformation. The finite element method was used to analyze creep buckling of circular cylindrical shells without initial imperfection. The number of circumferential waves obtained from the analyses agrees well with those of the experiments. The present experimental investigation shows that the circumferential waves are suddenly caused near a bulge. It is also found that there is no correlation between the wavelength of the circumferential waves observed at creep buckling and that of the circumferential initial imperfection. Deformation patterns at the bifurcation creep buckling obtained from the analyses are analogous to those of the experiments. It is concluded from the analyses and the experiments that the circumferential waves observed in creep buckling experiments are due to bifurcation buckling during creep deformation.

1987 ◽  
Vol 109 (2) ◽  
pp. 179-183 ◽  
Author(s):  
N. Miyazaki

The finite element method is applied to the creep buckling of circular cylindrical shells under axial compression. Not only the axisymmetric mode but also the bifurcation mode of the creep buckling are considered in the analysis. The critical time for creep buckling is defined as either the time when a slope of a displacement versus time curve becomes infinite or the time when the bifurcation buckling occurs. The creep buckling analyses are carried out for an infinitely long and axially compressed circular cylindrical shell with an axisymmetric initial imperfection and for a finitely long and axially compressed circular cylindrical shell. The numerical results are compared with available analytical ones and experimental data.


1979 ◽  
Vol 46 (4) ◽  
pp. 883-888 ◽  
Author(s):  
S. Murakami ◽  
E. Tanaka

Creep buckling of axially compressed circular cylindrical shells with axisymmetric initial imperfection is discussed with special emphasis on the general features of its unstable process. An elastic-creep material obeying the isotropic elastic law and the time-hardening creep law of Mises-Mises type is assumed. The analysis is performed quasi-statically on the basis of the variational principle of Reissner’s type and the finite deformation theory in Lagrangean formulation. In order to minimize the number of parameters necessary for specifying the problem, the basic equations are expressed in terms of nondimensional equations. An approximate expression for the limit time of creep buckling is also given for wide range of the parameters.


Author(s):  
C T F Ross ◽  
T Johns ◽  
R M Stanton

A theoretical and an experimental investigation was made on the vibration of three machined circular cylindrical shells under external water pressure. The theoretical investigation was based on the finite element method, where the shell was modelled by a truncated thin-walled conical shell element and the surrounding fluid by an annular element which had a cross-section in the form of an eight-node isoparametric quadrilateral. Comparison between theory and experiment was good and showed that the resonant frequencies decreased with an increase in the externally applied water pressure.


1988 ◽  
Vol 110 (4) ◽  
pp. 533-537 ◽  
Author(s):  
R. K. Singal ◽  
K. Williams

The free vibrations of thick circular cylindrical shells and rings are discussed in this paper. The well-known energy method, which is based on the three-dimensional theory of elasticity, is used in the derivation of the frequency equation of the shell. The frequency equation yields resonant frequencies for all the circumferential modes of vibration, including the breathing and beam-type modes. Experimental investigations were carried out on several models in order to assess the validity of the analysis. This paper first describes briefly the method of analysis. In the end, the calculated frequencies are compared with the experimental values. A very close agreement between the theoretical and experimental values of the resonant frequencies for all the models was obtained and this validates the method of analysis.


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