Difference between revisions of "Plate buckling"
Jump to navigation
Jump to search
| Line 1: | Line 1: | ||
= Eigenvalue methods for computing buckling loads = | = Eigenvalue methods for computing buckling loads = | ||
Plate and shell buckling loads are classically computed by solving the eigenvalue problem <math> \mathbf{K} - \lambda \mathbf{G}(\mathbf{N}) </math> where <math> \mathbf{K}</math> is the shell's/plate's stiffness and <math> \mathbf{G}(\mathbf{N}) </math> is its geometric stiffness, dependent on the in-plane (membrane) "stresses", and <math> \lambda </math> is the proportional load factor. | Plate and shell buckling loads are classically computed by solving the eigenvalue problem <math> \mathbf{K} - \lambda \mathbf{G}(\mathbf{N}) </math> where <math> \mathbf{K}</math> is the shell's/plate's stiffness and <math> \mathbf{G}(\mathbf{N}) </math> is its geometric stiffness, dependent on the in-plane (membrane) "stresses", and <math> \lambda </math> is the proportional load factor. | ||
To compute the buckling load in FEAP, one first solves for the membrane stresses and shell stiffness, then one forms the geometric stiffness, and finally one uses an eigensolver to determine the buckling load(s). | |||
The basic MARCO commands are as follows: | |||
<pre> | |||
TANGent,,1 | |||
GEOMetric | |||
SUBSpace,,5 | |||
</pre> | |||
Optionally one can use <code>ARPAck,,5</code> (if optionally built). | |||
Revision as of 02:56, 25 May 2022
Eigenvalue methods for computing buckling loads
Plate and shell buckling loads are classically computed by solving the eigenvalue problem where is the shell's/plate's stiffness and is its geometric stiffness, dependent on the in-plane (membrane) "stresses", and is the proportional load factor.
To compute the buckling load in FEAP, one first solves for the membrane stresses and shell stiffness, then one forms the geometric stiffness, and finally one uses an eigensolver to determine the buckling load(s).
The basic MARCO commands are as follows:
TANGent,,1 GEOMetric SUBSpace,,5
Optionally one can use ARPAck,,5 (if optionally built).