New developments of the rotation-free triangle for the analysis of thin shells and membranes

OÑATE EUGENIO; FLORES FERNANDO G.

Montpellier

Simposio; IASS 2004 Shells and Spatial Structures from model to realization; 2004

IASS

This paper shows applications of a recently developed shell element to the analysis of thin shells and membrane structures. The element is a three node triangle with only translational DOFs (rotation free) that uses the configuration of the three adjacent elements to evaluate the strains. This allows to compute (constant) bending strains and (linear) membrane stains. A total Lagrangian formulation is used. Strains are defined in terms of the principal stretches. This allows to consider rubber materials and other type of materials using the Hencky stress-strain pair. An explicit central difference scheme is used to integrate the momentum equations. Several examples, including inflation and deflation of membranes, show the excellent convergence properties and robustness of the element for large strain analysis of thin shells and membranes