Code_Aster
®
Version
5.0
Titrate:
SSNV136 - Triaxial compression test drained with model CJS (level 2)
Date:
05/02/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.136-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: V6.04.136
SSNV136 - Triaxial compression test drained with model CJS
(level 2)
Summary
This test makes it possible to validate level 2 of model CJS. It is about a triaxial compression test in drained condition.
calculations are carried out only on the solid part of the ground, without hydraulic coupling. The level of
containment is of 100 kPa.
By reason of symmetry, one is interested only in the eighth of a sample 3D subjected to a triaxial compression test.
It is about a test of nonregression. Nevertheless, results obtained with Code_Aster for model CJS2
are compared with those obtained with a private version of software FLAC - 2D.
Code_Aster
®
Version
5.0
Titrate:
SSNV136 - Triaxial compression test drained with model CJS (level 2)
Date:
05/02/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.136-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
X
y
E
L
H
C
With
B
Co-ordinates of the points (in meters):
With
B
C
X 0. 0.
0.5
y 0. 1.
0.5
Z 0. 0.
0.5
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:
xx
yy
zz
0
0
0
=
=
, by imposing the pressure of
containment corresponding on the front, side straight line and higher faces. Displacements are
locked on the faces postpones (
U
X
= 0
), side left (
U
y
= 0
) and lower (
U
Z
= 0
).
Phase 2:
One maintains displacements locked on the faces postpones (
U
X
= 0
), side left (
U
y
= 0
) and
lower (
U
Z
= 0
), as well as the confining pressure on the front faces and side straight line. One
apply a displacement imposed to the higher face:
()
U T
Z
, in order to obtain a deformation
zz
= - 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:
SSNV136 - Triaxial compression test drained with model CJS (level 2)
Date:
05/02/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.136-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
The results obtained with the software a private version of the software Flac-2D are used as reference.
2.2
Results of reference
Stresses
xx
,
yy
and
zz
at points A, B and C.
2.3
Uncertainty on the solution
Uncertainty related to the software Flac-2D.
2.4 Bibliography
[1]
Board, “FLAC (Fast Lagrangian Analysis off Continued) Version 2.20. U.S. NRC”,
NUREG/CR-5430, October 1989.
[2]
“Flac Fast Lagrangian Analysis off Continued. Theory and Background. ” Itasca Consulting
Group.
Code_Aster
®
Version
5.0
Titrate:
SSNV136 - Triaxial compression test drained with model CJS (level 2)
Date:
05/02/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.136-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
X
y
B
Cutting: 2 in height, in width and thickness.
Loading of phase 1:
Confining pressure:
xx
yy
zz
0
0
0
=
=
: successively 100 kPa, 200 kPa and 400 kPa.
Level 2 of model CJS
3.2
Characteristic of the mesh
A number of nodes: 27
A number of meshs and types: 8
HEXA8
and 24
QUA4
3.3 Functionalities
tested
Controls
DEFI_MATERIAU CJS
STAT_NON_LINE COMP_INCR
RELATION
“CJS”
Code_Aster
®
Version
5.0
Titrate:
SSNV136 - Triaxial compression test drained with model CJS (level 2)
Date:
05/02/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.136-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
xx
yy
zz
0
0
0
=
=
: 100 kPa
Localization Number
of command
deformation
axial
zz
(%)
stress
(kPa)
Reference
Aster %
difference
Not A, B and C
0.8%
xx
100.0
100.013 <
0.05
20.0
%
xx
100.0 100.020
< 0.05
0.8%
yy
100.0
100.013 <
0.05
20.0
%
yy
100.0 100.020
< 0.05
0.8%
zz
286.8
286.838 <
0.05
1.6
%
zz
332.9
332.965 <
0.05
3.2
%
zz
350.8
350.894 <
0.05
7.2
%
zz
356.1
356.144 <
0.05
20.0
%
zz
358.8
358.849 <
0.05
4.2 Parameters
of execution
Version:
5.02.16
Machine:
SGI-ORIGIN 2000-R12000
Overall dimension memory: 128 MO
Time CPU To use: 172s
Code_Aster
®
Version
5.0
Titrate:
SSNV136 - Triaxial compression test drained with model CJS (level 2)
Date:
05/02/02
Author (S):
C. CHAVANT, pH. AUBERT
Key
:
V6.04.136-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 values of the stresses obtained with Aster coincide with those of software FLAC with one
lower deviation than 0,05%.