====== E2GDP ======

===== Description =====

Elastic constitutive law for solid elements at constant temperature. Second gradient-plane deformation (for second gradient method from Grenoble).

==== The model ====

This law is used for mechanical analysis of elastic isotropic solids undergoing large strains. \\
Implemented by: P. Besuelle, 2002

==== Files ====

Prepro: LE2GDP.F \\
Lagamine: E2GDP.F (plane strain state), E2GDPS.F (plane stress state ?)

===== Availability =====

|Plane stress state| NO |
|Plane strain state| YES|
|Axisymmetric state| NO |
|3D state| NO |
|Generalized plane state| NO |

===== Input file =====

==== Parameters defining the type of constitutive law ====

^ Line 1 (2I5, 60A1)^^
|IL|Law number|
|ITYPE| 582|
|COMMENT| Any comment (up to 60 characters) that will be reproduced on the output listing|

==== Integer parameters ====

^ Line 1 (1I5) ^^
|ISOL| = 0 : use of total stresses in the constitutive law |
|:::| $\neq$ 0 : use of effective stresses in the constitutive law. See [[appendices:a8|Appendix 8]] |

==== Real parameters ====

^ Line 1 (2G10.0) ^^
|E| Elastic modulus |
|RHO| Specific mass |

===== Stresses =====

==== Number of stresses ====

8 \\

==== Meaning ====


The stresses are the components of 2$^{nd}$ gradient stress tensor in global (X, Y, Z) coordinates. \\

|SIG(1)|$\Sigma_{111}$|
|SIG(2)|$\Sigma_{112}$|
|SIG(3)|$\Sigma_{121}$|
|SIG(4)|$\Sigma_{122}$|
|SIG(5)|$\Sigma_{211}$|
|SIG(6)|$\Sigma_{212}$|
|SIG(7)|$\Sigma_{221}$|
|SIG(8)|$\Sigma_{222}$|


===== State variables =====

==== Number of state variables ====
2

==== List of state variables ====


|Q(1)| = 1 in plane strain state |
|Q(2)| RHO actualised specific mass |