|
|
||
|
|
|
|
From:
http://www.fgg.uni-lj.si/kmk/esdep/media/wg08/f0900007.jpg
(buckling course material, ESDEP WG 8, Plates and Shells, Lecture 8.9: Design of Stringer-Stiffened Cylindrical Shells"
SUMMARY: The buckling behaviour of stiffened shell structures is presented and the different types of failure are discussed. The shell has to be designed with respect to local shell buckling (limited to the shell panel between the stiffeners) and the stiffened panel buckling (or bay instability) in which both the shell panel and the stringers participate. Buckling of the stringers themselves must also be prevented. The design procedure relevant to this problem, as proposed by ECCS recommendations [1], is presented.
INTRODUCTION: In Lectures 8.6 and Lecture 8.7 several aspects that influence the structural behaviour of shells have been introduced and the main principles of the shell theory have been presented. In particular it has been shown how the buckling strength of shell structures is influenced by residual stresses, geometric imperfections, and in some cases by the eccentricity of the load and by the boundary conditions. For these reasons axially compressed cylindrical shells often fail at a buckling strength considerably lower than the theoretical elastic value.
The buckling strength of cylindrical shells is often improved by the use of circumferential and/or longitudinal stiffeners. Their size, spacing and position on the outside or inside of the cylinder surface are factors that complicate the buckling behaviour of the shell.
In this lecture the general aspects of the buckling behaviour of stiffened shells are presented and, as an example of the application of practical design procedures, the buckling behaviour of stringer stiffened axially compressed cylinders is treated.
Related material in the same course on plates and shells:
Lecture 8.1: Introduction to Plate Behaviour and Design
Lecture 8.6: Introduction to Shell Structures
Lecture 8.7: Basic Analysis of Shell Structures
Lecture 8.8: Design of Unstiffened Cylinders
Page 107 / 227