2D timber beam modeling / analysis

Hello,

Can somebody, please, give me some advice on writing a command file for the following problem:
I want to model static mechanical 2D plane stress problem (thickness = 45mm) with orthotropic material.
I've tried using MODELISATION = D_PLAN but I cannot access the ELAS_ORTHO material option.

Do I need to use a diferent modelisation to access this option? if So, What Do you recomend.

Thanks in advance,
Vito

Ciao Vito
for plane stress use C_PLAN (MODELISATION = D_PLAN is plane deformation). Here is an example. Good luck
Johannes

mail-file, containing ONE Quad4-element and 4 nodes:

---

TITRE NOM=INDEFINI
AUTEUR=INTERFACE_IDEAS DATE=10/09/2007
FINSF
%
COOR_2D NOM=INDEFINI NBOBJ=4 NBLIGE=5 NBLIGT=11
NUMIN=1 NUMAX=4
AUTEUR=INTERF_ST/TF DATE=10/09/2007
% XMAX= 0.10000000E+01 YMAX= 0.10000000E+01
% XMIN= 0.00000000E+00 YMIN= 0.00000000E+00
%FORMAT=(1*NOM_DE_NOEUD,2*COORD)
N1 0.00000000000000E+00 0.00000000000000E+00
N2 1.00000000000000E+00 0.00000000000000E+00
N3 1.00000000000000E+00 1.00000000000000E+00
N4 0.00000000000000E+00 1.00000000000000E+00
FINSF
%
QUAD4 NOM=INDEFINI NBOBJ=1 NBLIGE=3 NBLIGT=6
NUMIN=1 NUMAX=1
AUTEUR=INTERF_ST/TF DATE=10/09/2007
%FORMAT=(1*NOM_DE_MAILLE,4*NOM_DE_NOEUD)
M1 N1 N2 N3 N4
FINSF
%
GROUP_MA NOM=ALL_ELM NBOBJ=1 NBLIGE=3 NBLIGT=6
NUMIN=1 NUMAX=1
AUTEUR=INTERF_ST/TF DATE=10/09/2007
%FORMAT=(1*NOM_DE_MAILLE)
M1
FINSF
%
GROUP_NO NOM=ALL_NOD NBOBJ=4 NBLIGE=3 NBLIGT=5
NUMIN=1 NUMAX=4
AUTEUR=INTERF_ST/TF DATE=10/09/2007
%FORMAT=(1*NOM_DE_NOEUD)
N1 N2 N3 N4
FINSF
%
FIN

---

and here comm-file, for a lin static analysis with 2 load cases:

DEBUT();

PRE_IDEAS();

MeshLin=LIRE_MAILLAGE(FORMAT='ASTER',);

FEMLin=AFFE_MODELE(MAILLAGE=MeshLin,
AFFE=_F(TOUT='OUI',
PHENOMENE='MECANIQUE',
MODELISATION='C_PLAN',),);

ortho=DEFI_MATERIAU(ELAS_ORTH=_F(E_L=300000,
E_T=200000,
E_N=100000,
NU_LT=0,
G_LT=0,),
INFO=2,);

Mat=AFFE_MATERIAU(MAILLAGE=MeshLin,
MODELE=FEMLin,
AFFE=_F(TOUT='OUI',
MATER=ortho,),);

thickn=AFFE_CARA_ELEM(MODELE=FEMLin,
INFO=1,
MASSIF=_F(GROUP_MA='ALL_ELM',
ANGL_REP=0,),);

Bc1=AFFE_CHAR_MECA(MODELE=FEMLin,
DDL_IMPO=(_F(NOEUD='N1',
DX=0.0,
DY=0.0,),
_F(NOEUD='N2',
DY=0,),
_F(NOEUD='N4',
DX=0,),),
INFO=1,);

X_FORCE=AFFE_CHAR_MECA(MODELE=FEMLin,
FORCE_NODALE=_F(NOEUD=('N2','N3',),
FX=50,),);

Y_FORCE=AFFE_CHAR_MECA(MODELE=FEMLin,
FORCE_NODALE=_F(NOEUD=('N3','N4',),
FY=50,),);

X_Solut=MECA_STATIQUE(MODELE=FEMLin,
CHAM_MATER=Mat,
CARA_ELEM=thickn,
EXCIT=(_F(CHARGE=Bc1,),
_F(CHARGE=X_FORCE,),),);

Y_Solut=MECA_STATIQUE(MODELE=FEMLin,
CHAM_MATER=Mat,
CARA_ELEM=thickn,
EXCIT=(_F(CHARGE=Bc1,),
_F(CHARGE=Y_FORCE,),),);

IMPR_RESU(MODELE=FEMLin,
RESU=(_F(RESULTAT=X_Solut,
NOM_CHAM='DEPL',),
_F(RESULTAT=Y_Solut,
NOM_CHAM='DEPL',),),);

FIN(FORMAT_HDF='OUI',);