D modeling
==============

Characteristics of the mesh
----------------------------

Mesh: the mesh is composed of two superimposed QUAD4 cells with four nodes (:math:`\mathit{N1}`, :math:`\mathit{N2}`, :math:`\mathit{N3}`, :math:`\mathit{N4}`). One of the meshes is intended to model a DKT element and the other is intended to model a GRILLE_EXCENTRE element.


.. image:: images/1000000000000270000002902F67A4BE09F6D24C.png
    :width: 2.4925in
    :height: 2.6445in


.. _RefImage_1000000000000270000002902F67A4BE09F6D24C.png:

The eccentric grid mesh has four integration points and a single subpoint.

• Node group :math:`\mathit{ENC}` is composed of nodes :math:`\mathit{N1}` and :math:`\mathit{N2}`

• Node group :math:`\mathit{CHA}` is composed of nodes :math:`\mathit{N3}` and :math:`\mathit{N4}`


Characteristics of modeling
------------------------

Modeling:

MO= AFFE_MODELE (MAILLAGE =MA,

 AFFE =(

     _F (GROUP_MA =' PLA ', PHENOMENE =' MECANIQUE', MODELISATION =' DKT '),

     _F (GROUP_MA =' GRI ', PHENOMENE =' MECANIQUE',

         MODELISATION =' GRILLE_EXCENTRE ',))

)

Boundary conditions:

BLOCAGE = AFFE_CHAR_MECA (MODELE =MO,

 DDL_IMPO =_F (GROUP_NO =' ENC ',

 DX=0.0, DY=0.0, DZ=0.0, DRX =0.0, =0.0, DRY =0.0, DRZ =0.0,),

)

Mechanical loading:

CHARGE = AFFE_CHAR_MECA (MODELE =MO,

 FORCE_NODALE =_F (GROUP_NO =' CHA ', FX=0, FX=0, FZ=-100. ),

)

Assignment of the characteristics of the elements:

PLAQUE = AFFE_CARA_ELEM (MODELE =MO,

 COQUE =_F (GROUP_MA =( 'PLA'), EPAIS =0.05,),

 GRILLE =_F (GROUP_MA =( 'GRI'), SECTION = 0.01, EXCENTREMENT = 0.05,

     ANGL_REP =( 10,10),),

)


Tested values and results
----------------------------

.. csv-table::

    "Coordinated
    mesh QUA2 ", "Point
    integration", "sub-point", "**Reference**"
    "COOR_X ", "1", "1", "1", "0.334844823"
    "COOR_Y ", "1", "1", "1", "0.265331216"
    "COOR_Z ", "1", "1", "1", "0.208012702"


Tolerance is :math:`1.0E-03` for all tests.