0
Research Papers: Design and Analysis

Buckling Design of Confined Steel Cylinders Under External Pressure

[+] Author and Article Information
Daniel Vasilikis

Department of Mechanical Engineering, University of Thessaly, Volos 38334, Greecedavasili@mie.uth.gr

Spyros A. Karamanos

Department of Mechanical Engineering, University of Thessaly, Volos 38334, Greeceskara@mie.uth.gr

J. Pressure Vessel Technol. 133(1), 011205 (Dec 23, 2010) (9 pages) doi:10.1115/1.4002540 History: Received June 09, 2010; Revised August 26, 2010; Published December 23, 2010; Online December 23, 2010

Thin-walled steel cylinders surrounded by an elastic medium, when subjected to uniform external pressure may buckle. In the present paper, using a two-dimensional model with nonlinear finite elements, which accounts for both geometric and material nonlinearities, the structural response of those cylinders is investigated, toward developing relevant design guidelines. Special emphasis is given on the response of the confined cylinders in terms of initial imperfections; those are considered in the form of initial out-of-roundness of the cylinder and as an initial gap between the cylinder and the medium. Furthermore, the effects of the deformability of the surrounding medium are examined. The results indicate significant imperfection sensitivity and a strong dependency on the medium stiffness. The numerical results are employed to develop a simple and efficient design methodology, which is compatible with the recent general provisions of European design recommendations for shell buckling and could be used for design purposes.

Copyright © 2011 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Schematic representation of the buckling problem of an externally pressurized cylinder confined by the surrounding medium

Grahic Jump Location
Figure 2

Finite element model of cylinder-medium system

Grahic Jump Location
Figure 3

Schematic representation of a confined ring with (a) gap-type initial imperfection and (b) out-of-roundness initial imperfection

Grahic Jump Location
Figure 4

Response of rigidly confined elastic cylinders under external pressure in the absence of initial imperfections

Grahic Jump Location
Figure 5

Comparison between numerical results and analytical predictions from Glock’s Eq. 1 for the buckling (ultimate) pressure of rigidly confined elastic cylinders

Grahic Jump Location
Figure 6

Consecutive deformation shapes of a tightly fitted elastic cylinder; configuration (b) corresponds to the stage that ultimate pressure occurs

Grahic Jump Location
Figure 7

Buckling pressure of imperfect elastic cylinders over the buckling pressure of the corresponding perfect elastic cylinders: (a) effects of initial out-of-roundness and (b) effects of initial gap

Grahic Jump Location
Figure 8

Imperfection sensitivity of elastic rigidly confined cylinders under external pressure; finite element results and predictions of Eq. 8

Grahic Jump Location
Figure 9

Response of tightly fitted steel cylinders (g/R=0) embedded in a rigid confinement medium; finite element results for different values of initial out-of-roundness (δ0/R)

Grahic Jump Location
Figure 10

Effects of initial out-of-roundness (δ0/R) and initial gap (g/R) on the maximum pressure sustained by a confined steel cylinder embedded in a rigid confinement medium (E′/E=10−1)

Grahic Jump Location
Figure 11

Effects of initial out-of-roundness (δ0/R) and D/t ratio on the maximum pressure sustained by a confined steel cylinder embedded in a rigid confinement medium (E′/E=10−1, g/R=0)

Grahic Jump Location
Figure 12

Variation of maximum pressure pmax steel cylinders embedded in a rigid confinement medium with respect to the slenderness parameter λ defined in Eq. 10; finite element results and predictions of Eqs. 12,13,14

Grahic Jump Location
Figure 13

Comparison between numerical results and analytical predictions from Montel’s simplified equation 3(12)

Grahic Jump Location
Figure 14

Structural response of perfect steel cylinders for different values of confinement medium modulus (E′/E); pressure versus deformation equilibrium paths (g/R=0, δ0/R=0)

Grahic Jump Location
Figure 15

Effects of initial out-of-roundness (δ0/R) and stiffness of confinement medium (E′/E) on the maximum pressure sustained by a confined steel cylinder (D/t=200): (a) tightly fitted cylinders (g/R=0) and (b) cylinders with gap (g/R=5.4×10−3)

Grahic Jump Location
Figure 16

Comparison between elastic and steel cylinders (D/t=200) with respect to the E′/E value for: (a) perfect cylinders (δ0/R=g/R=0), (b) δ0/R=0.012, g/R=0, and (c) δ0/R=0, g/R=0.0027.

Grahic Jump Location
Figure 17

Variation of maximum pressure with respect to the E′/E value for perfect steel cylinders (δ0/R=g/R=0) and different values of D/t ratio

Grahic Jump Location
Figure 18

Comparison between numerical results and analytical prediction from Eq. 18 for the maximum pressure with respect to the E′/E value

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In