Reference Solution
=====================


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+ .. image:: images/100000000000030D000002E0F153CB3F3DC70C85.png                                                              + .. image:: images/100000000000030F000002EEAF23BC7F5D4A56D2.png                                                              +
|    :width: 3.1492in                                                                                                         |    :width: 3.1492in                                                                                                         |
+    :height: 2.9646in                                                                                                        +    :height: 3.0161in                                                                                                        +
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.. _Ref152059234:


.. _Ref87774704:

**Figure** 1 **:** Willam test results for (:math:`{\mathrm{\sigma }}_{\mathit{xx}}` on the left, :math:`{\mathrm{\sigma }}_{\mathit{yy}}` on the right)

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+ .. image:: images/1000000000000308000002D175A954765F4553F6.png                                                              + .. image:: images/1000000000000296000001E57A0A1F53DB49C2C1.png                                                              +
|    :width: 3.1492in                                                                                                         |    :width: 3.3465in                                                                                                         |
+    :height: 2.9291in                                                                                                        +    :height: 2.4528in                                                                                                        +
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.. _Ref1520592341:


.. _Ref877747041:

Figure 2: Willam test results for (:math:`{\mathrm{\sigma }}_{\mathit{xy}}` on the left) and the BETON_RAG model (on the right)

It can be seen that the stress :math:`{\mathrm{\sigma }}_{\mathit{yy}}` is low, due to an effect of initial cracking in the :math:`\mathrm{xx}` direction. We also notice a change of sign for the :math:`{\sigma }_{\mathrm{xy}}` constraint characteristic of anisotropic models. This test confirms the ability of the model to converge when a rotation of the main stress directions is applied.


1.
    * **Bibliographical references**

Shahrockh Ghavamian, Ignacio Carol, Arnaud Delaplace, "Discussions over MECA project results", French Journal of Civil Engineering, Volume 7 of 2003, page 543-581