Code_Aster
®
Version
5.0
Titrate:
SSNV155 - Triaxial compression test drained on a turned sample of an angle of
/6
Date:
04/03/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.155-A
Page:
1/6
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A
Organization (S):
EDF/AMA, CNEPE
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
Document: V6.04.155
SSNV155 - Triaxial compression test drained on a sample
turned of an angle from pi/6 compared to axis X with
model CJS (level 2)
Summary
This test makes it possible to supplement the validation of level 2 of model CJS already approached in the case test SSNV136.
It corresponds to the digital simulation of the same test (drained triaxial compression test) on same material but with
a different geometry. The sample tested is thus turned of an angle of
/6 compared to axis X. By
consequent, directions X, y, Z are not any more main directions. That makes it possible to validate the operations
of numerical integration of the model which acts on the nondiagonal terms of the tensors of the deformations and
stresses.
As for the case test SSNV136, calculations are carried out only on the solid part of the ground, without
hydro-mechanical coupling. By reason of symmetry, one is interested only in the eighth of a sample subjected to
a triaxial compression test. The level of containment is of 400 kPa
It is about a test of nonregression. The results obtained are compared with those provided by an Aster calculation
with a mesh whose axes of symmetry are the axes of co-ordinates. They correspond to them exactly with
the rotation of angle
/6 near.
Code_Aster
®
Version
5.0
Titrate:
SSNV155 - Triaxial compression test drained on a turned sample of an angle of
/6
Date:
04/03/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.155-A
Page:
2/6
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A
1
Problem of reference
1.1 Geometry
Z
y
X
E
L
H
With
/6
B
C
D
E
F
G
H
Co-ordinates of the points (in meters):
With
B
C
D
X 0. 0.
1. 1.
y 0. 0.8660254037844
5
0.8660254037844
5
0.
Z 0. 0.5
0.5
0.
1.2
Material property
E = 35,6616541 10
3
kPa
= 0,15037594
Parameters CJS2:
= - 0,55
= 0,82
R
m
= 0,289
R
C
= 0,265
N = 0,6
K
COp
= 25,5 10
3
kPa
With = 0.25 kPa P
has
= - 100 kPa
1.3
Initial conditions, boundary conditions, and loading
Phase 1:
One brings the sample in a homogeneous state, by imposing the corresponding confining pressure
on faces EFGH, CDHG and BCGF. Normal displacements are locked on faces ABCD,
ADHE and ABFE.
Phase 2:
One maintains displacements normal locked on faces ABCD, ADHE and ABFE; as well as
confining pressure on faces CDHG and BCGF. An imposed normal displacement is applied
on face EFGH, in order to obtain a deformation according to the normal direction equalizes with 20%
(counted starting from the beginning of phase 2).
height:
H = 1 m
width:
L
= 1 m
thickness:
E = 1 m
Code_Aster
®
Version
5.0
Titrate:
SSNV155 - Triaxial compression test drained on a turned sample of an angle of
/6
Date:
04/03/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.155-A
Page:
3/6
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A
2
Reference solution
2.1
Method of calculation used for the reference solution
By taking account of the rotation of angle of the sample, results obtained by a calculation Aster with
a mesh whose axes of symmetry are the axes of co-ordinates, are used as reference.
2.2
Results of reference
Stresses
xx
,
yy
,
zz
and
yx
at point A.
2.3
Uncertainty on the solution
Code_Aster
®
Version
5.0
Titrate:
SSNV155 - Triaxial compression test drained on a turned sample of an angle of
/6
Date:
04/03/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.155-A
Page:
4/6
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A
3 Modeling
With
3.1
Characteristics of modeling
3D:
Z
y
X
Cutting: 1 in height, in width and thickness.
Loading of phase 1:
Confining pressure: 400 kPa.
Level 2 of model CJS
3.2
Characteristic of the mesh
A number of nodes: 8
A number of meshs and types: 1
HEXA8
and 6
QUA4
3.3 Functionalities
tested
Controls
DEFI_MATERIAU CJS
STAT_NON_LINE COMP_INCR
RELATION
“CJS”
Code_Aster
®
Version
5.0
Titrate:
SSNV155 - Triaxial compression test drained on a turned sample of an angle of
/6
Date:
04/03/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.155-A
Page:
5/6
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A
4
Results of modeling A
4.1 Values
tested
For containment: 400 kPa
Localization Number
of command
deformation
axial
zz
(%)
stress
(kPa)
Reference
Aster %
difference
Not A
2.0%
xx
400.0 400.000
<
10
6
10.0
%
xx
400.0 400.000
< 10
6
20.0
%
xx
400.0 400.000
< 10
6
2.0
%
yy
54.0613
54.061292 <
10
6
10.0
%
yy
63.5278 63.527785 < 10
6
20.0
%
yy
65.0989 65.098864 < 10
6
2.0
%
zz
82.1839 82.18387
< 10
6
10.0
%
zz
110.583 110.58335
< 10
6
20.0
%
zz
115.297 115.29659
< 10
6
2.0
%
yz
24.3549 24.354871 < 10
6
10.0
%
yz
40.7513 40.751319 < 10
6
20.0
%
yz
43.4725 43.472508 < 10
6
4.2 Parameters
of execution
Version:
5.03.08
Machine;
SGI-ORIGIN2000-R12000
System:
IRIX64
Overall dimension memory: 128 Mo
Time CPU To use:
83s
Code_Aster
®
Version
5.0
Titrate:
SSNV155 - Triaxial compression test drained on a turned sample of an angle of
/6
Date:
04/03/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.155-A
Page:
6/6
Manual of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A
5
Summary of the results
The results are in perfect agreement with those of the reference.