But
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This operator calculates the following fracture mechanics quantities, in 2D and 3D for non-meshed cracks (method X- FEM):


* the rate of energy restoration by the theta method in the case of a linear or non-linear thermo-elastic problem [:ref:`R7.02.01 <R7.02.01>`] and [:ref:`R7.02.03 <R7.02.03>`], in statics or in dynamics [:external:ref:`R7.02.02 <R7.02.02>`], and in elastoplasticity [:external:ref:`R7.02.07 <R7.02.07>`];


* stress intensity factors :math:`\mathrm{K1}`, :math:`\mathrm{K2}` and :math:`\mathrm{K3}` using the method of singular displacements in the case of a linear thermo-elastic problem [:ref:`R7.02.05 <R7.02.05>`];


* the maximization of :math:`G` and :math:`\mathrm{K1}` under limited constraints.

Before first use, it is advisable to refer to the corresponding reference documents and advice for use, in particular the document [:ref:`U2.05.01 <U2.05.01>`].

This operator generates a table_sdaster concept.