Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
1/8

Organization (S): EDF-R & D/AMA
Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
V3.01.116 document

SSLL116 - Treillis reinforced 3D

Summary:

This test relates to the study of a lattice made up of hurled beams, in linear static analysis.

The lattice is modelled with elements linear (SEG2) and subjected to a specific loading and the effect of
gravity.

There is a modeling with a first geometry, then a modeling with bars of reinforcement.

This test is an example with didactic aiming since it shows the construction of the solution by finite elements rather
to use MECA_STATIQUE directly.

Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
2/8

1
Problem of reference

1.1 Geometry
2,8

Y

Z
21

7

X

With

7
0,7

1,05

The lattice consists of annular beams of sections everywhere (R=0.05, ep=0.02), except on the part
“crane”, made up of circular sections of two sizes: R=0.05 for the full rounds and R=0.07
for the hatched round.
Point A is in the middle of the final stem.

1.2
Material properties

Isotropic linear elastic material:

E = 1.962 E11 Pa;=0.3

1.3
Boundary conditions and loadings

The base of the lattice is embedded.

Loadings

Vertical nodal force in a:
Fy = ­ 20e6 NR
Field of gravity (according to X)
G = ­ 9.81 m/s ²
Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
3/8

2
Reference solution

2.1
Results of reference

Displacements and rotations of node A (DEPL).
The results calculated in this case test result from a former execution of Aster. It is a case test
of nonregression.

Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
4/8

3 Modeling
With

3.1
Characteristics of modeling

2,8

Y

Z
21

7

X

With

7
0,7

1,05


·
Modeling POU_D_T
·
No reinforcements

3.2
Characteristics of the grid

The grid is obtained by GMSH.

A number of nodes:
247
A number of meshs:
267

3.3 Functionalities
tested

Commands Options
PRE_GMSH

LIRE_MAILLAGE

DEFI_MATERIAU ELAS

AFFE_MATERIAU ALL

AFFE_MODELE
“MECHANICAL” “POU_D_T'

DEFI_VALEUR

AFFE_CARA_ELEM
BEAM “RINGS”

AFFE_CHAR_MECA DDL_IMPO

FORCE_NODALE

CALC_MATR_ELEM “RIGI_MECA”

CALC_VECT_ELEM “CHAR_MECA”

NUME_DDL MATR_RIGI

ASSE_MATRICE

ASSE_VECTEUR

FACT_LDLT

RESO_LDLT

DEFUFI

IMPR_RESU “GMSH”

TEST_RESU “NON_REGRESSION”

Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
5/8

4
Results of modeling A

4.1 Values
tested

Loading Value
tested
Aster
Force concentrated vertical in A
Displacement of A Dx
7,20564x10­1

Displacement of A Dy
­ 2,02277x10­0

Displacement of A Dz
­ 1,12417x10­0

Rotation of A Drx
9,88004x10­1

Rotation of A Dry
1,83637x10­1

Rotation of A Drz
­ 1,12592x10­1

4.2 Remarks

It is seen that the not-symmetry of the arrow of the lattice involves displacements according to Z, although
force applied is it according to Y and X only (force of gravity)
Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
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5 Modeling
B

5.1
Characteristics of modeling

2,8

Y

Z

21
7

X

With

7
0,7

1,05



·
Modeling POU_D_T
·
Bars of reinforcement

5.2
Characteristics of the grid

The grid is obtained by GMSH.

A number of nodes:
265
A number of meshs:
287

5.3 Functionalities
tested

Commands Options
PRE_GMSH

LIRE_MAILLAGE

DEFI_MATERIAU ELAS

AFFE_MATERIAU ALL

AFFE_MODELE
“MECHANICAL” “POU_D_T'

DEFI_VALEUR

AFFE_CARA_ELEM
BEAM “RINGS”

AFFE_CHAR_MECA DDL_IMPO

FORCE_NODALE

CALC_MATR_ELEM “RIGI_MECA”

CALC_VECT_ELEM “CHAR_MECA”

NUME_DDL MATR_RIGI

ASSE_MATRICE

ASSE_VECTEUR

FACT_LDLT

RESO_LDLT

DEFUFI

IMPR_RESU “GMSH”

TEST_RESU “NON_REGRESSION”
Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
7/8

6
Results of modeling B

6.1 Values
tested

Loading Value
tested
Aster
Force concentrated vertical in A
Displacement of A Dx
6,61627x10­1

Displacement of A Dy
­ 1,82145x10­0

Displacement of A Dz
­ 2,6628x10­1

Rotation of A Drx
8,48048x10­1

Rotation of A Dry
1,68397x10­1

Rotation of A Drz
­ 9,43511x10­2

6.2 Remarks

The reinforcements made it possible to decrease displacements of the arrow of the lattice.
Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Code_Aster ®
Version
7.1
Titrate:
SSLL116 - Treillis articulated 3D

Date
:

23/09/03
Author (S):
Mr. Key ABBAS
:
V3.01.116-A Page:
8/8

7
Summary of the results

This example shows a way of carrying out the “didactic” calculation of manner while building
explicitly vectors and matrices necessary for a standard calculation by finite elements.
Handbook of Validation
V3.01 booklet: Linear statics of the linear structures
HT-66/03/008/A

Outline document