B modeling
==============


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

2D modeling in plane deformations. This modeling corresponds to methodology 2 of the U2.04.06 documentation: excavation with support with stress initialization by calling CREA_CHAMP and deconfinement using a single model and a "flexible" material for the excavated area.

The mesh is the same as for modeling A.


Calculation process
---------------------

The objective of this test case is to test a method. The following table shows the main steps that structure the command file.


.. csv-table::

    "**Orders**", "**Reviews**"
    "CREA_CHAMP ", "Initialization of geostatic constraints (here isotropic :math:`5\mathrm{MPa}` in compression)"
    "STAT_NON_LINE ", "Blocking the nodes in the gallery to calculate the nodal reactions to be injected to simulate deconfinement"
    "CREA_CHAMP ", "Recovery of nodal reactions"
    "STAT_NON_LINE ", "Reinjecting nodal reactions"
    "STAT_NON_LINE ", "Progressive deconfinement of the Massif"



Tested sizes and results
------------------------------

After the installation of the coating (final moment), the components :math:`{\sigma }_{\mathrm{xx}}` and :math:`{\sigma }_{\mathit{yy}}` are tested at the nodes :math:`\mathrm{N2}` and :math:`\mathrm{N6}` as well as the radial displacement at these points (:math:`\mathrm{DX}` for :math:`\mathrm{N2}`, :math:`\mathrm{DY}` for :math:`\mathit{N6}`).


+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|                                                                                   |**Reference**|**Aster**   |**Difference (%)**|
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|**Knot** :math:`\mathrm{N2}`                                                       |             |            |                  |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|                                                                                   |-1,52821.106 |-1,53619.106|0.52              |
+ .. image:: images/Object_90.svg                                                   +             +            +                  +
|    :width: 28                                                                     |             |            |                  |
+    :height: 24                                                                    +             +            +                  +
|                                                                                   |             |            |                  |
+                                                                                   +             +            +                  +
|                                                                                   |             |            |                  |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|                                                                                   |-8,47179,106 |-8.53167.106|0.71              |
+ .. image:: images/Object_91.svg                                                   +             +            +                  +
|    :width: 28                                                                     |             |            |                  |
+    :height: 24                                                                    +             +            +                  +
|                                                                                   |             |            |                  |
+                                                                                   +             +            +                  +
|                                                                                   |             |            |                  |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|:math:`\mathrm{DX}`                                                                |-1,6925.10-3 |-1,6687.10-3|-1.41             |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|**Knot** :math:`\mathrm{N6}`                                                       |             |            |                  |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|                                                                                   |-8,47179,106 |-8,41158.106|-0.71             |
+ .. image:: images/Object_102.svg                                                  +             +            +                  +
|    :width: 28                                                                     |             |            |                  |
+    :height: 24                                                                    +             +            +                  +
|                                                                                   |             |            |                  |
+                                                                                   +             +            +                  +
|                                                                                   |             |            |                  |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|                                                                                   |-1,52821.106 |-1,52967.106|0.1               |
+ .. image:: images/Object_103.svg                                                  +             +            +                  +
|    :width: 28                                                                     |             |            |                  |
+    :height: 24                                                                    +             +            +                  +
|                                                                                   |             |            |                  |
+                                                                                   +             +            +                  +
|                                                                                   |             |            |                  |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+
|:math:`\mathrm{DY}`                                                                |-1,6925.10-3 |-1.7180.10-3|1.51              |
+-----------------------------------------------------------------------------------+-------------+------------+------------------+