Modeling A
--------------

.. _Toc93483755:

Characteristics of modeling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



We calculate the FS and locate the non-circular fracture surface using
the Morgenstern-Price method of the CALC_STAB_PENTE macro command.
Knowing that the fracture surface passes through the weak layer
if :math:`\lambda ={c}_{2}/{c}_{1}\ll 1`,
We define the areas to search for the points
of the end of the fracture surface as being
the ends of the weak layer on the slope profile,
Let ``X1_ MINI = 1.8``, ``X1_ MAXI = 2.4``, ``X2_ MINI = 15.6`` and ``X2_ MAXI = 16.2``.

.. note::

    Based on prior tests, algorithm EFWA finds the optimum in 10 iterations
    approximately. So, we're taking some margin with "ITER_MAXI = 30".

The result of the critical surface divided into 5 slices is shown in :numref:`fig3-modeleA`.


.. figure:: images/10000000000004420000017A8112FF8D0BBE9D8C.png
 :name: FIG3-ModelA
    :width: 70%

    **Break surface from CALC_STAB_PENTE**

.. _RefImage_10000000000004420000017A8112FF8D0BBE9D8C.png:



.. _Toc93483756:


Tested sizes and results
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The safety factor is tested at the last refinement of the mesh.
The results are shown in :ref:`Tableau 2<table2_v603007>`.



.. _table2_v603007 :

**Table 2**: FS reference values (Modeling A)

.. csv-table::
 :name: tab-1
    :header-rows: 1
    :widths: auto
    :align: center

    "**NUME_RAFF**", "**Identification**", "**Aster Result**", "**Reference Value**", "**Error**"
    "4", "FS", "0.481604", "0.5"," 3.2%"


Since algorithm EFWA is a probabilistic algorithm,
it is normal to observe a slight deviation from the FS obtained.
Therefore, the comparison accuracy is increased reasonably (10%).


Summary of results
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The FS result from macro-order CALC_STAB_PENTE gives the difference of 3.2%
compared to the reference solution. This proves the relevance of the result
of the Morgenstern-Price method and the EFWA algorithm in CALC_STAB_PENTE.