Code_Aster
®
Version
4.0
Titrate:
SSLL12 Lattice of bars under three stresses
Date:
19/01/98
Author (S):
J.M. PROIX, L. VIVAN
Key:
V3.01.012-A
Page:
1/6
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
HI-75/96/039 - Ind A
Organization (S):
EDF/IMA/MN, CISI
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
Document: V3.01.012
SSLL12 - Lattice of bars under three stresses
Summary:
Static response in linear mechanics of the structures of a triangulated system of pin jointed struts (plane lattice)
under 3 stresses:
·
displacement of support,
·
specific forces,
·
effect of dilation.
This test makes it possible to validate the element
BAR
under various cases of loading. It validates also the option
LIAISON_OBLIQUE
control
AFFE_CHAR_MECA
.
Code_Aster
®
Version
4.0
Titrate:
SSLL12 Lattice of bars under three stresses
Date:
19/01/98
Author (S):
J.M. PROIX, L. VIVAN
Key:
V3.01.012-A
Page:
2/6
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
HI-75/96/039 - Ind A
1
Problem of reference
1.1 Geometry
5 m
5 m
5 m
5 m
5 m
5 m
5 m
4 m
With
C
D
4 m
B
y, v
X, U
1.2
Material properties
Isotropic linear elastic material:
E = 2.1 E+11 AP
Linear expansion factor:
=
1. E05 °C
1
1.3
Boundary conditions and loadings
Hinge of A (U
With
= v
With
= 0).
Support with roller out of B and C (v
B
= v'
C
= 0).
Code_Aster
®
Version
4.0
Titrate:
SSLL12 Lattice of bars under three stresses
Date:
19/01/98
Author (S):
J.M. PROIX, L. VIVAN
Key:
V3.01.012-A
Page:
3/6
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
HI-75/96/039 - Ind A
1.4 Conditions
initial
Office plurality of 3 stresses:
·
displacement of support: v
With
= 0.02 m, v
B
= 0.03 m, v'
C
= 0.015 m
·
specific forces: F
E
= 150 kN, F
F
= 100 kN
·
effect of dilation of all the bars for a variation in temperature of 30°C compared to
temperature of assembly (geometry of reference).
With
C
B
F
E
F
E
F
F
V
With
V
B
V'
C
v'
u'
2
Reference solution
2.1
Method of calculation used for the reference solution
Determination of the unknown the hyperstatic one by the method of cut to know the tensile load.
2.2
Results of reference
Not
Size and unit
Value
Data base
Tensile load (NR)
8.2112 E+03
2.3
Uncertainty on the solution
Analytical solution.
2.4 References
bibliographical
[1]
Mr. LAREDO, Resistance of materials, Paris, Dunod, 1970, p. 579.
Code_Aster
®
Version
4.0
Titrate:
SSLL12 Lattice of bars under three stresses
Date:
19/01/98
Author (S):
J.M. PROIX, L. VIVAN
Key:
V3.01.012-A
Page:
4/6
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
HI-75/96/039 - Ind A
3 Modeling
With
3.1
Characteristics of modeling
Type of modeling used: element
BAR
.
With
C
B
A1
A2
A1
A1
A1
A1
A2
A2
A2
A2
A2
A2
A1
A1
A1
D
A2
A2
3.2
Characteristics of the mesh
= 30°.
A1 = 1.41 E03 m
2
.
A2 = 2.82 E03 m
2
.
3.3 Functionalities
tested
Controls
Keys
AFFE_CHAR_MECA
DDL_IMPO
[U4.25.01]
LIAISON_OBLIQUE
FORCE_NODALE
TEMP_CALCULEE
MECA_STATIQUE
[U4.31.01]
CALC_ELEM
EFGE_ELNO_DEPL
[U4.61.02]
Code_Aster
®
Version
4.0
Titrate:
SSLL12 Lattice of bars under three stresses
Date:
19/01/98
Author (S):
J.M. PROIX, L. VIVAN
Key:
V3.01.012-A
Page:
5/6
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
HI-75/96/039 - Ind A
4
Results of modeling A
4.1 Values
tested
Identification
Reference
Aster
% difference
Charge: thermal dilation
Option:
“EFGE_ELNO_DEPL”
Net M10, Noeud: B, Cmp: NR
12946.
1.29541 E+04
0.063
Net M16, Noeud: C, Cmp: NR
4285.2
4.28926 E+03
0.095
Net M17, Noeud: C, Cmp: NR
10189.
1.02076 E+04
0.183
Charge: specific forces
Option:
“DEPL”
Node: E, Cmp: DY
1.0566 E02
1.05800 E02
0.133
Option:
“EFGE_ELNO_DEPL”
Net M10, Noeud: B, Cmp: NR
87137.
8.71128 E+04
0.028
Net M16, Noeud: C, Cmp: NR
24158.
2.41596 E+04
0.007
Net M17, Noeud: C, Cmp: NR
57524.
5.74954 E+04
0.050
Charge: imposed displacements
Option:
“EFGE_ELNO_DEPL”
Net M10, Noeud: B, Cmp: NR
65979.1
6.59757 E+04
0.005
Net M16, Noeud: C, Cmp: NR
21839.1
2.18453 E+04
0.029
Net M17, Noeud: C, Cmp: NR
51925.6
5.19877 E+04
0.120
Charge: office plurality of the 3 stresses
Option:
“EFGE_ELNO_DEPL”
Net M10, Noeud: B, Cmp: NR
8211.2
8.18302 E+03
0.343
Net M16, Noeud: C, Cmp: NR
50282
5.02942 E+04
0.024
Net M17, Noeud: C, Cmp: NR
1.1964 E+05
1.19691 E+05
0.043
4.2 Remarks
No deformation of bending intervenes in the calculation of the solution.
4.3 Parameters
of execution
Version: 3.02.11
Machine: CRAY C90
Overall dimension memory:
8 MW
Time CPU To use:
60 seconds
Code_Aster
®
Version
4.0
Titrate:
SSLL12 Lattice of bars under three stresses
Date:
19/01/98
Author (S):
J.M. PROIX, L. VIVAN
Key:
V3.01.012-A
Page:
6/6
Manual of Validation
V3.01 booklet: Linear statics of the linear structures
HI-75/96/039 - Ind A
5
Summary of the results
The variations compared to the references are lower than 0.18% for the stresses (dilation
thermics, specific face, imposed displacement) separate and lower than 0.34% when these
stresses are cumulated.