Plane or axisymmetric state
Mechanical analysis, Grenoble 2nd gradient method, in large deformations.
The element is defined by 9 nodes specified in NODES in the order indicated in the figure. Nodes 1, 3, 5, and 7 have 6 DoF ($u_1$, $u_2$, $v_{11}$, $v_{12}$, $v_{21}$, $v_{22}$), whereas nodes 2, 4, 6, and 8 only have 2 DoF ($u_1$, $u_2$). The central node 9 has 4 DoF ($\lambda_{11}$, $\lambda_{12}$, $\lambda_{21}$, $\lambda_{22}$), that have a different signification from ($v_{11}$, $v_{12}$, $v_{21}$, $v_{22}$) but occupy the same position.
Type: 207
Implemented by: P. Besuelle, J-P. Radu (2002)
Prepro: SGRA2A.F
Lagamine: SGRA2B.F
Title (A5) | |
---|---|
TITLE | “SGRA2” in the first 5 columns |
Control data (3I5) | |
NELEM | Number of elements |
ISPSMAS | 0 |
INSIG | = 0 → No initial stress = 1 or 2 → Initial stresses |
Initial stresses - Only if INSIG > 0 (4G10.0) | |
If INSIG=1: $\sigma_y=\sigma_{y0}+yd\sigma_{y}$ If INSIG=2: $\sigma_y=min(\sigma_{y0}+yd\sigma_y,0)$ |
|
SIGY0 | $\sigma_{y0}$ effective stress $\sigma_y$ at the axes origin |
DSIGY | Effective stress gradient along Y axis |
AK0X | $k_0$ ratio $\sigma_x/\sigma_y$ |
AK0Z | $k_0$ ratio $\sigma_z/\sigma_y$ (if AK0Z=0, AK0Z=AK0X) |
Definition of the elements (6I5/9I5) | |
NINTE | Number of integration points (1, 4, or 9) |
LMATM | “Classic” mechanical law |
LMATF | “Second gradient” material law |
NODES(9) | List of nodes |
Stresses (in global axes):
4 “classic” mechanical stresses: $\sigma_x$, $\sigma_y$, $\sigma_{xy}$, $\sigma_z$
8 “second gradient” mechanical stresses: $\Sigma_{111}$, $\Sigma_{112}$, $\Sigma_{121}$, $\Sigma_{122}$, $\Sigma_{211}$, $\Sigma_{212}$, $\Sigma_{221}$, $\Sigma_{222}$
Internal variables:
Internal variables of the “classic” mechanical law
Internal variables of the “second gradient” mechanical law