Implementation of a simple wrinkling model into argyris’ membrane finite element

This paper presents the implementation of a simple wrinkling/slackening model into the classical Argyris membrane element, comparing the solution performance by Newton’s iterations, using either the tangent stiffness matrix (numerically evaluated through a finite-difference approximation), or a secant stiffness matrix (obtained through the modification of the elasticity matrix, according to a projection technique which decompose deformations into elastic and wrinkle components)