Code_Aster ®
Version
5.0

Titrate:
SSNV155 - Triaxial Essai drained on a turned sample of an angle of ­/6 Date:
04/03/02
Author (S):
C. CHAVANT, pH. Key AUBERT
:
V6.04.155-A Page:
1/6

Organization (S): EDF/AMA, CNEPE
Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
Document: V6.04.155
SSNV155 - Triaxial Essai 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 from ­/6 compared to axis X. By
consequent, directions X, y, Z are not any more principal 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
constraints.
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 a Aster calculation
with a grid whose axes of symmetry are the axes of co-ordinates. They correspond to them exactly with
the rotation of angle ­/6 near.

Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A

Code_Aster ®
Version
5.0

Titrate:
SSNV155 - Triaxial Essai drained on a turned sample of an angle of ­/6 Date:
04/03/02
Author (S):
C. CHAVANT, pH. Key AUBERT
:
V6.04.155-A Page:
2/6

1
Problem of reference

1.1 Geometry
Z
/6th
F
H
height:
H = 1 m
width:
L
= 1 m
thickness:
E = 1 m
H
G
With
y
B
X
D
E
L
C


Co-ordinates of the points (in meters):

With
B
C
D
X 0. 0.
1. 1.
y 0. 0.8660254037844
0.8660254037844
0.
5
5
Z 0. ­ 0.5
­ 0.5
0.

1.2
Material property

E = 35,6616541 103 kPa
= 0,15037594
Parameters CJS2:
= - 0,55
= 0,82
Rm = 0,289
Rc = 0,265
N = 0,6

K p
O = 25,5 103 kPa
With = 0.25 kPa Pa = - 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 blocked on faces ABCD,
ADHE and ABFE.

Phase 2:
One maintains displacements normal blocked 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).
Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A

Code_Aster ®
Version
5.0

Titrate:
SSNV155 - Triaxial Essai drained on a turned sample of an angle of ­/6 Date:
04/03/02
Author (S):
C. CHAVANT, pH. Key AUBERT
:
V6.04.155-A Page:
3/6

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 Aster calculation with
a grid whose axes of symmetry are the axes of co-ordinates, are used as reference.

2.2
Results of reference

Constraints xx, yy, zz and yx at point A.

2.3
Uncertainty on the solution

Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A

Code_Aster ®
Version
5.0

Titrate:
SSNV155 - Triaxial Essai drained on a turned sample of an angle of ­/6 Date:
04/03/02
Author (S):
C. CHAVANT, pH. Key AUBERT
:
V6.04.155-A Page:
4/6

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 grid

A number of nodes: 8
A number of meshs and types: 1 HEXA8 and 6 QUA4

3.3 Functionalities
tested

Commands




DEFI_MATERIAU CJS



STAT_NON_LINE COMP_INCR
RELATION
“CJS”


Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A

Code_Aster ®
Version
5.0

Titrate:
SSNV155 - Triaxial Essai drained on a turned sample of an angle of ­/6 Date:
04/03/02
Author (S):
C. CHAVANT, pH. Key AUBERT
:
V6.04.155-A Page:
5/6

4
Results of modeling A

4.1 Values
tested

For containment: ­ 400 kPa

Localization Numéro deformation
constraint
Reference
Aster %
difference
of command
axial
(kPa)
zz (%)
Not A

­ 2.0%
xx
­ 400.0 ­ 400.000
<
10­6

­ 10.0
%
xx
­ 400.0 ­ 400.000
< 10­6

­ 20.0
%
xx
­ 400.0 ­ 400.000
< 10­6

­ 2.0
% yy
­ 54.0613
­ 54.061292 <
10­6

­ 10.0
%
yy
­ 63.5278 ­ 63.527785 < 10­6

­ 20.0
%
yy
­ 65.0989 ­ 65.098864 < 10­6

­ 2.0
% zz
­ 82.1839 ­ 82.18387
< 10­6

­ 10.0
%
zz
­ 110.583 ­ 110.58335
< 10­6

­ 20.0
%
zz
­ 115.297 ­ 115.29659
< 10­6

­ 2.0
%
yz
­ 24.3549 ­ 24.354871 < 10­6

­ 10.0
%
yz
­ 40.7513 ­ 40.751319 < 10­6

­ 20.0
%
yz
­ 43.4725 ­ 43.472508 < 10­6

4.2 Parameters
of execution

Version:
5.03.08


Machine;
SGI-ORIGIN2000-R12000
System:
IRIX64
Obstruction memory: 128 Mo
Time CPU To use:
83s

Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A

Code_Aster ®
Version
5.0

Titrate:
SSNV155 - Triaxial Essai drained on a turned sample of an angle of ­/6 Date:
04/03/02
Author (S):
C. CHAVANT, pH. Key AUBERT
:
V6.04.155-A Page:
6/6

5
Summary of the results

The results are in perfect agreement with those of the reference.
Handbook of Validation
V6.04 booklet: Nonlinear statics of the voluminal structures
HT-66/02/001/A

Outline document