Application of the finite element method to Koiter's asymptotic postbuckling theory often leads to numerical problems. Generally it is believed that these problems are due to locking of non-linear terms of different orders. A general method is given here that explains the reason for the numerical problems and eliminates these problems. The reason for the numerical problems is that the postbuckling stresses are inaccurately determined. By including a local stress contribution, the postbuckling stresses are calculated correctly. The present method gives smooth postbuckling stresses and shows a quick convergence of the postbuckling coefficients. (C) 1998 John Wiley & Sons, Ltd.
|Journal||International Journal for Numerical Methods in Engineering|
|Publication status||Published - 30 Jun 1998|
- asymptotic postbuckling
- finite element method
- smooth stresses