Stability Behaviour of Shells and Imperfection Sensitivity by the Asymptotic Numerical Method

Sébastien Baguet (1) , Bruno Cochelin (2)

1 LaMCoS - Laboratoire de Mécanique des Contacts et des Structures [Villeurbanne]
2 LMA - Laboratoire de Mécanique et d'Acoustique [Marseille]

This paper is concerned with stability behaviour and imperfection sensitivity of thin elastic shells. The aim is to determine the reduction of the critical buckling load as a function of the imperfection amplitude. For this purpose, the direct calculation of the so-called fold line connecting all the limit points of the equilibrium branches when the imperfection varies is performed. This fold line is the solution of an extended system demanding the criticality of the equilibrium. The Asymptotic Numerical Method is used as an alternative to Newton-like incremental-iterative procedures for solving this extended system. It results in a very robust and efficient path-following algorithm that takes the singularity of the tangent stiffness matrix into account. A modern and efficient finite shell element is considered for the discretiza-tion. The underlying shell theory uses the EAS concept. It allows finite rotations as well as thickness stretch. A numerical example involving a shape imperfection is presented.

Mots clés: Buckling; Thin Shells; imperfection sentivity; extended system; Asymptotic Numerical Method

Domaines: Mécanique des structures [physics.class-ph]; Mécanique des structures [physics.class-ph]

Sébastien Baguet, Bruno Cochelin. Stability Behaviour of Shells and Imperfection Sensitivity by the Asymptotic Numerical Method. WCCM V, Fifth World Congress of Computational Mechanics, Jul 2002, Vienna, Austria. 10pp. ⟨hal-00623495⟩