.. _R3.08.07:

**r3.08.07** Elements MEMBRANE and GRILLE_MEMBRANE
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**Summary:**

This document describes the formulation and implementation of elements MEMBRANE and GRILLE_MEMBRANE in*Code_Aster*. Elements MEMBRANE make it possible to model any linear membrane behavior or a non-linear behavior of isotropic membranes. Elements GRILLE_MEMBRANE are finite elements more specifically dedicated to the representation of steel reinforcements in a mass (for civil engineering applications such as reinforced concrete). The main characteristics of these elements are as follows:


* membrane elements, without torsional stiffness;


* no degrees of freedom of rotation, but in return no possibility of eccentricity;


* surface geometric support (triangle, quadrangle; linear or quadratic, and biquadratic only for MEMBRANE);

Elements GRILLE_MEMBRANE make it possible to model the non-linear behavior of reinforcing bars.


.. toctree::
    :hidden:

    self

.. toctree::
    :maxdepth: 2
    :numbered:

    Introduction
    Formulation_lin_aire_des__l_ments_de_MEMBRANE
    Formulation_non_lin_aire_des__l_ments_de_MEMBRANE
    Formulation_des__l_ments_de_GRILLE_MEMBRANE
    Matrice_de_masse
    Bibliographie
    Description_des_versions_du_document