Code_Aster ®
Version
7.4
Titrate:
SSNP115 ­ Validation of LIRE_RESU and DEPL_CALCULE

Date:
02/11/05
Author (S):
Key J.M. PROIX
:
V6.03.115-A Page:
1/4

Organization (S): EDF-R & D/AMA
Handbook of Validation
V6.03 booklet: Nonlinear statics of the plane systems
V6.03.115 document

SSNP115 ­ Validation of LIRE_RESU and
DEPL_CALCULE on the elastoplastic calculation of one
plate perforated

Summary:

This test 2D in plane constraints quasi-static makes it possible to illustrate on a simple case (treated in addition in
[V6.03.114] reading and exploitation of results via LIRE_RESU and the continuation in STAT_NON_LINE
(DEPL_CALCULE).

It is about a homogeneous rectangular plate, perforated in its center, consisted of an elastoplastic material
with isotropic work hardening, whose initial state is nonconstrained, which is subjected to a traction at its ends.
One is interested in the elastoplastic solution in load. More precisely, the analytical methods allow
to know a lower limit of the limiting load. By an elastoplastic calculation, one would like to find one
limit higher.

Modeling B makes it possible to read the result with format MED (via LIRE_RESU) and comprises commands of
examination on the fields read.

Modeling C makes it possible to validate the procedure to carry out the calculation of the constraints and variables
interns starting from the displacements read by LIRE_RESU (PREDICTION=' DEPL_CALCULE').
Handbook of Validation
V6.03 booklet: Nonlinear statics of the plane systems
HT-66/05/005/A

Code_Aster ®
Version
7.4
Titrate:
SSNP115 ­ Validation of LIRE_RESU and DEPL_CALCULE

Date:
02/11/05
Author (S):
Key J.M. PROIX
:
V6.03.115-A Page:
2/4

1
Problem of reference

1.1 Geometry

The problem is identical to that treated in [V6.03.114]. One models only one quarter of
plate because of symmetries.


P
G
F


G
F

H=150

With

a=10

With

B
D


B
D

L=100

1.2
Properties of materials

Elastoplastic behavior with isotropic work hardening given by the traction diagram.

Young modulus E = 1000 Mpa (modeling C)
Young modulus E = 200000 Mpa (modeling B)
NAKED Poisson's ratio = 0.3
Traction diagram (prolongation constant right)

Epsilon 0.004 0.006 0.009
0.02
Sigma 4.
5. 5.5 6.

These values are to be multiplied per 1000 for modeling B.

1.3
Boundary conditions and loadings

Loading
In this case (second reading partial or total of the solution) no loading is used.

2
Reference solution

2.1 Solution
elastoplastic

The reference solution is that of test FORMA03A [V6.03.114].

Handbook of Validation
V6.03 booklet: Nonlinear statics of the plane systems
HT-66/05/005/A

Code_Aster ®
Version
7.4
Titrate:
SSNP115 ­ Validation of LIRE_RESU and DEPL_CALCULE

Date:
02/11/05
Author (S):
Key J.M. PROIX
:
V6.03.115-A Page:
3/4

3 Modeling
B

3.1
Characteristics of modeling

Modeling C_PLAN. A quarter of the plate is modelled. Reading of the fields of displacements and
constraints with format MED.

3.2
Characteristics of the grid



One uses a grid with format MED [SSNP115]. It comprises 186 QUAD8 and 617 nodes.

3.3 Functionalities
tested

Commands



LIRE_MAILLAGE FORMAT
MED

LIRE_RESU FORMAT_MED NOM_CHAM
DEPL
LIRE_RESU FORMAT_MED NOM_CHAM
SIEF_ELNO_ELGA
CALC_NO OPTION SIEF_NOEU_ELGA

MACR_LIGN_COUP NOM_CHAM
SIEF_NOEU_ELGA
POST_RELEVE_T ACTION
REPERE
POLAIRE

4
Results of modeling B

4.1 Values
tested

It is checked that the values read are correct: one tests for that the value of displacement following Y
at the point G as well as component SIYY at the same point.

Moment
GROUP_NO
Identification Reference
Aster Difference
(%)

1.4 G
Displacement
DY
1.4. 1.4
0.

1.4 G
Constraint
SIXX
541.57 541.57
0
Handbook of Validation
V6.03 booklet: Nonlinear statics of the plane systems
HT-66/05/005/A

Code_Aster ®
Version
7.4
Titrate:
SSNP115 ­ Validation of LIRE_RESU and DEPL_CALCULE

Date:
02/11/05
Author (S):
Key J.M. PROIX
:
V6.03.115-A Page:
4/4

5 Modeling
C

5.1
Characteristics of modeling

Modeling C_PLAN. A quarter of the plate is modelled. Reading of the fields of displacements with
format IDEAS.

5.2
Characteristics of the grid

The grid is identical to that of modeling A.

5.3 Functionalities
tested

Commands



LIRE_RESU FORMAT_MED
NOM_CHAM
DEPL
DEFI_MATERIAU TRACTION


STAT_NON_LINE COMP_INCR
RELATION
“VMIS_ISOT_TRAC”
STAT_NON_LINE NEWTON
PREDICTION
DEPL_CALCULE
CALC_ELEM
OPTION
SIEF_ELNO_ELGA
VARI_ELNO_ELGA
EQUI_ELGA_SIGM
EPSI_ELNO_DEPL
CALC_NO
OPTION
SIEF_NOEU_ELGA
RECU_FONCTION
NOM_CHAM
DEPL
CURVED IMPR_FONCTION
FONCTION


6
Results of modeling C

6.1 Values
tested

Constraint SIYY at the point G for a force distributed of 5.2 Mpa. The value of reference results from
test FORMA03A.

Moment Identification Reference Aster Difference
(%)
5.2 SIYY 5.202
5.202
0.

7
Summary of the results

This test makes it possible to check the correct operation of LIRE_RESU on a result of STAT_NON_LINE
(fields of displacements and constraints).

It also makes it possible to validate operation “DEPL_CALCULE” allowing starting from the only field
solution displacement, to quickly find (without iteration of Newton) the solutions in constraints
and internal variables. This can be useful to save place of storage for calculations
bulky.

Handbook of Validation
V6.03 booklet: Nonlinear statics of the plane systems
HT-66/05/005/A