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--- doc:user:elements:volumes:elements_formulation [2014/10/20 17:16] – [EAS Formulation] joris
+++ doc:user:elements:volumes:elements_formulation [2018/11/27 08:42] (current) – [EAS Formulation] boman
@@ Line 9: / Line 9: @@
 ===== Selective Reduced Integration =====
-The classical solution to the locking issue, experienced when using the [[#Standard formulation]], is to use elements with selective reduced integration (''CAUCHYMECHVOLINTMETH = VES_CMVIM_SRI'') : the pressure is seen as constant over the element, and calculated in its center (which means that the pressure is calculated on one integration point only).
+The classical solution to the locking issue, experienced when using the [[#Standard formulation]], is to use elements with selective reduced integration (''CAUCHYMECHVOLINTMETH = VES_CMVIM_SRI'') : the pressure is seen as constant over the element, and computed in its center (which means that the pressure is computed on one integration point only).
 <note> **Selective Reduced Integration** is different from **Full Reduced Integration**. Indeed, when using **Full Reduced Integration**, both pressure and deviatoric stresses are integrated on one integration point, located at the center of the element. This integration method induces //hourglass// modes, which are purely numerical modes leading to a degradation of the mesh.
 </note>
-When using **Selective Reduced Integration**, pressure is calculated at the element center but deviatoric stresses are calculated using 4 integration points in 2D and 8 in 3D. This way, //Hourglass// modes are prevented.
+When using **Selective Reduced Integration**, pressure is computed at the element center but deviatoric stresses are computed using 4 integration points in 2D and 8 in 3D. This way, //Hourglass// modes are prevented.
 The integration of internal forces is done with the formula:
@@ Line 31: / Line 31: @@
 ===== Selective Reduced Integration with Pressure Report =====
-Integrating the pressure using only one integration point leads to inaccuracies due to an erroneous estimation of the element volume (this can become quite significant in axisymmetric near the revolution axis or when the mesh is highly distorted). The solution consists in calculating the pressure at the element center. Then, since its value is constant over the element, it can be integrated at each integration point used to calculate deviatoric stresses. Therefore, the pressure is reported at these integration point to calculate the pressure integral using these four points. This method (''CAUCHYMECHVOLINTMETH = VES_CMVIM_SRIPR'') is the default one.
+Integrating the pressure using only one integration point leads to inaccuracies due to an erroneous estimation of the element volume (this can become quite significant in axisymmetric near the revolution axis or when the mesh is highly distorted). The solution consists in calculating the pressure at the element center. Then, since its value is constant over the element, it can be integrated at each integration point used to compute deviatoric stresses. Therefore, the pressure is reported at these integration point to compute the pressure integral using these four points. This method (''CAUCHYMECHVOLINTMETH = VES_CMVIM_SRIPR'') is the default one.
 ===== EAS Formulation=====
@@ Line 38: / Line 38: @@
  - integer parameters : ''EASS'', ''EASV'', ''KEAS'', ''UEAS'', ''IEAS'', ''TEAS'', ''EEAS''
  - double parameters (''PEAS'').
+<note warning>EAS is not implemented for 2D axisymmetric problems!</note>