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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
1/12

Organization (S): EDF-R & D/AMA, SAMTECH, INSA-LYON

Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
Document: V3.03.108

SSLS108 - Helicoid Coque under load
concentrated

Summary:

This test in linear elasticity is very severe from its geometry (left hull). Two first
modelings correspond one to the element of QUAD of modeling COQUE_3D (MEC3QU9H) and
the other with element TRI7 of modeling COQUE_3D (MEC3TR7H). The two following ones relate to
modeling SHB8.

The values of reference are computation results provided in the literature and the comparison
calculation/reference relates to displacement in a point of the structure. One notes variations compared to
reference lower than 0.15% for element MEC3QU9H and lower than 0.4% for element MEC3TR7H.
For modelings SHB8, the stupid maximum changes of 1.4% with 24 elements SHB8 (modeling C) and
0.3% with 96 SHB8 (modeling D).
Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

Code_Aster ®
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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
2/12

1
Problem of reference

1.1 Geometry

Y
FY
L
C
H
O
B
With
X
Z
B
FZ


The hull is thickness 0.32 m, length 12 m and of width 1.1 Mr.

1.2
Material properties

E = 29. 106 Pa
= 0.22

1.3
Boundary conditions and loadings

Embedded on side OBC: U = v = W = 0, X = y = Z = 0

Two loading cases which corresponds to loadings concentrated at point a:

·
Force parallel with axis Z; Fz = 1 NR
·
Force parallel with the axis Y; Fy = 1 NR

Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

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SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
3/12

2
Reference solution

2.1
Method of calculation used for the reference solution

Parameters of the problem and results of reference (solutions obtained by finite elements of
beam type) are given in the reference below [bib1].

2.2
Results of reference

Displacement of point A following Y
Displacement of point A following Z.

2.3 References
bibliographical

[1]
BATOZ J.L., DHATT G.: Modeling of the structures by finite elements. Volume 3 hulls,
p456-459 (1992).

Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
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:
V3.03.108-B Page:
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3 Modeling
With

3.1
Characteristics of modeling

Element of hull 3D MEC3QU9H

B
O
C
With


Cutting:

2 according to the width, 12 according to the length
24 meshs QUAD9, thickness: H = 0.32

Names of the nodes:

Not O
N06
Not B
N01
Not C
N02
Not A
N032

3.2
Characteristics of the grid

A number of nodes: 125
A number of meshs and types: 24 QUAD9

3.3 Functionalities
tested

Commands




AFFE_CARA_ELEM HULL
TOUT


AFFE_CHAR_MECA DDL_IMPO
GROUP_NO


FORCE_NODALE
GROUP_NO
AFFE_MODELE AFFE
MODELISATION
:
“COQUE_3D”

DEFI_MATERIAU ELAS



Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
5/12

4
Results of modeling A

4.1 Values
tested

Case of
Not
Size in unit
Reference
Aster %
difference
loads
Fz = 1 NR
With
displacement V (m)
­ 1.72 10­3 ­ 1.717
10­3
­ 0.15


displacement W (m)
5.42 10­3 5.411
10­3
­ 0.16
Fy = 1 NR
With
displacement V (m)
1.75 10­3 1.750
10­3
0.0


displacement W (m)
­ 1.72 10­3 ­ 1.717
10­3
­ 0.15

Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
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5 Modeling
B

5.1
Characteristics of modeling

Element of hull MEC3TR7H



Cutting:

2 according to the width, 12 according to the length
48 meshs TRIA7, thickness: H = 0.32

Names of the nodes:

Not O
N06
Not B
N01
Not C
N02
Not A
N032

5.2
Characteristics of the grid

A number of nodes: 173
A number of meshs and types: 48 TRIA7

5.3 Functionalities
tested

Commands




AFFE_CARA_ELEM HULL
TOUT


AFFE_CHAR_MECA DDL_IMPO
GROUP_NO


FORCE_NODALE
GROUP_NO
AFFE_MATERIAU ALL



“MECHANICAL” AFFE_MODELE “COQUE_3D”
TOUT

DEFI_MATERIAU ELAS



Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

Code_Aster ®
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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
7/12

6
Results of modeling B

6.1 Values
tested

Case of
Not
Size in unit
Reference
Aster %
difference
loads
Fz = 1 NR
With
displacement V (m)
­ 1.72 10­3 ­ 1.714
10­3
­ 0.34


displacement W (m)
5.42 10­3 5.399
10­3
­ 0.38
Fy = 1 NR
With
displacement V (m)
1.75 10­3 1.746
10­3
­ 0.23


displacement W (m)
­ 1.72 10­3 ­ 1.714
10­3
­ 0.34

Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
8/12

7 Modeling
C

7.1
Characteristics of modeling

Element of hull MASSIF SHB8

B1
O1 C1
C2
A1
A2


Cutting:

2 according to the width, 12 according to the length
24 meshs SHB8, thickness: H = 0.32

Names of the nodes:

Not O1
N03
Not O2
N05
Not B1
N04
Not B2
N06
Not C1
N01
Not C2
N02
Not A1
N78
Not A2
N75

7.2
Characteristics of the grid

A number of nodes: 78
A number of meshs and types: 24 SHB8

7.3 Functionalities
tested

Commands



MODI_MAILLAGE ORIE_SHB8
GROUP_MA
TOUT
AFFE_CHAR_MECA DDL_IMPO
GROUP_NO

FORCE_NODALE
GROUP_NO
AFFE_MODELE AFFE
MODELISATION
:
SHB8
DEFI_MATERIAU ELAS



Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

Code_Aster ®
Version
7.2
Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
9/12

8
Results of modeling C

8.1 Values
tested

Case of
Not
Size in unit
Reference
Aster
% difference
loads
Fz = 1 NR
A1 and A2
displacement V (m)
­ 1.72 10­3
­ 1.717 10­3
0.16


displacement W (m)
5.42 10­3
5.408 10­3
­ 0.21
Fy = 1 NR
A1 and A2
displacement V (m)
1.75 10­3
1.726 10­3
­ 1.36


displacement W (m)
­ 1.72 10­3
­ 1.717 10­3
0.16

8.2 Remarks

A modeling 3D on the same grid (meshs HEXA8) revealed a blocking: results
are very far away from the reference. For example, in the case of load 1, one obtains:

Not
Size in unit
Reference
Aster
A1 and A2
displacement V (m)
­ 1.72 10­3
­ 7.5 10­4
displacement W (m)
5.42 10­3
5.408 10­3

This blocking does not appear any more with quadratic meshs HEXA20, since one obtains then:

Not
Size in unit
Reference
Aster
A1 and A2
displacement V (m)
­ 1.72 10­3
­ 1.729 10­3
displacement W (m)
5.42 10­3
5.43 10­3

Modeling SHB8 makes it possible to avoid any numerical blocking, at a cost (in time CPU) similar to
that of a grid HEXA8.
Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

Code_Aster ®
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Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
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9 Modeling
D

9.1
Characteristics of modeling

Element of hull MASSIF SHB8
B1D1O1E1C1
C2
A1
A2


Cutting:

4 according to the width, 24 according to the length
96 meshs SHB8, thickness: H = 0.32

Names of the nodes:

Not O1
N245
Not O2
N249
Not B1
N224
Not B2
N226
Not C1
N239
Not C2
N241
Not D1
N236
Not D2
N238
Not E1
N250
Not E2
N246
Not A1
N05
Not A2
N06

9.2
Characteristics of the grid

A number of nodes: 250
A number of meshs and types: 96 SHB8

9.3 Functionalities
tested

Commands



MODI_MAILLAGE ORIE_SHB8
GROUP_MA
TOUT
AFFE_CHAR_MECA DDL_IMPO
GROUP_NO

FORCE_NODALE
GROUP_NO
AFFE_MODELE AFFE
MODELISATION
:
SHB8
DEFI_MATERIAU ELAS



Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

Code_Aster ®
Version
7.2
Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
11/12

10 Results of modeling D

10.1 Values
tested

Case of
Not
Size in unit
Reference
Aster
% difference
loads
Fz = 1 NR
A1 and A2
displacement V (m)
­ 1.72 10­3
­ 1.718 10­3
0.09


displacement W (m)
5.42 10­3
5.41 10­3
­ 0.18
Fy = 1 NR
A1 and A2
displacement V (m)
1.75 10­3
1.744 10­3
­ 0.33


displacement W (m)
­ 1.72 10­3
­ 1.718 10­3
0.09

10.2 Remarks

A modeling 3D on the same grid (meshs HEXA8) revealed a blocking: even with
a grid with 96 elements. The results remain very far away from the reference. For example, for
loading case 1, one obtains:

Not
Size in unit
Reference
Aster
A1 and A2
displacement V (m)
­ 1.72 10­3
­ 2.49 10­4
displacement W (m)
5.42 10­3
1.12 10­3

This blocking does not appear any more with quadratic meshs HEXA20, since one obtains then:

Not
Size in unit
Reference
Aster
A1 and A2
displacement V (m)
­ 1.72 10­3
­ 1.735 10­3
displacement W (m)
5.42 10­3
5.438 10­3

With HEXA20, convergence is much better. Modeling SHB8 makes it possible to avoid all
numerical blocking, at a cost (in time CPU) similar to that of a grid HEXA8.
Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

Code_Aster ®
Version
7.2
Titrate:
SSLS108 - Helicoid Coque under concentrated loadings

Date:
03/11/03
Author (S):
P. MASSIN, J.M. PROIX, A. LAULUSA, Key S. BAGUET
:
V3.03.108-B Page:
12/12

11 Summary of the results

This test is very severe because of geometry of the hull which is left.

Good solutions are obtained for four modelings.

Handbook of Validation
V3.03 booklet: Linear statics of the plates and hulls
HT-66/03/008/A

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