Code_Aster ®
Version
7.4
Titrate:
Modeling SHB8
Date:
01/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER Key
:
U3.12.05-A Page
: 1/4
Organization (S): EDF-R & D/AMA, DeltaCAD
Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
Document: U3.12.05
Modeling SHB8
Summary:
This document describes for modeling SHB8:
· degrees of freedom carried by the finite elements which support modeling,
· the related meshs supports,
· supported loadings,
· non-linear possibilities,
· case-tests implementing modeling.
This modeling corresponds to element SHB8-PS (developed by Alain Combescure, S. Baguet, INSA
LYON) which is pressed on a mesh HEXA8. The element has 5 points of integration, distributed in the thickness.
It under-is integrated to have good performances. To avoid blockings the modes of hourglass are
stabilized by the “Assumed strain méthod”. It functions into linear, nonlinear geometrical and material
(behavior VMIS_ISOT_TRAC only).
Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
Code_Aster ®
Version
7.4
Titrate:
Modeling SHB8
Date:
01/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER Key
:
U3.12.05-A Page
: 2/4
1 Discretization
1.1
Degrees of freedom
Modeling
Ddl with all the nodes
SHB8
DX, DY, DZ
1.2
Net support of the matrices of rigidity
For modeling SHB8, the meshs support of the finite elements are hexahedrons with 8 nodes.
Modeling Nets
Interpolation
in
displacements
SHB8 HEXA8
Linear
1.3
Net support of the surface loadings
Modeling
Net
Interpolation in displacements
SHB8 QUAD4
linear
2 Loadings
supported
The loadings available are as follows:
· “FORCE_ARETE”
Allows to apply linear forces, with an edge of voluminal element.
· “FORCE_FACE”
Allows to apply surface forces to a voluminal face of element.
· “FORCE_INTERN”
Allows to apply voluminal forces.
· “PESANTEUR”
Allows to apply a loading of the gravity type.
· “PRES_REP”
Allows to apply a pressure to a field of continuous medium.
Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
Code_Aster ®
Version
7.4
Titrate:
Modeling SHB8
Date:
01/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER Key
:
U3.12.05-A Page
: 3/4
3 Possibilities
non-linear
3.1
Law of behavior
The law of behavior available under COMP_INCR in STAT_NON_LINE is defined by the relation
VMIS_ISOT_TRAC (cf [U4.51.11]).
3.2 Deformations
Deformations available, used in the relations of behavior under the key word
DEFORMATION in STAT_NON_LINE are (Cf. [U4.51.11]):
/“PETIT”
The deformations used for the relation of behavior are the deformations
linearized.
/“GREEN”
The deformations used in the relation of behavior are the deformations of
GREEN_LAGRANGE.
4
Examples of implementation: case-tests
· Linear statics
SSLS124A [V3.03.124]: Quasi-static analysis of a beam in inflection, embedded with one
end and subjected to a vertical force at the other end.
· Non-linear statics
SSNS101A [V6.05.101]: Analyze static non-linear geometrical (breakdown) of a panel
cylindrical under a specific force.
· Linear dynamics
SDLS109H [V2.03.109]: Seek Eigen frequencies and modes associated with a ring
cylindrical thick.
Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
Code_Aster ®
Version
7.4
Titrate:
Modeling SHB8
Date:
01/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER Key
:
U3.12.05-A Page
: 4/4
Intentionally white left page.
Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
Outline document