Code_Aster ®
Version
7.4
Titrate:
Operator MODE_STATIQUE

Date
:
01/02/05
Author (S):
Y. PONS, J. PIGAT Key
:
U4.52.14-G Page
: 1/6

Organization (S): EDF-R & D/AMA

Handbook of Utilization
U4.5- booklet: Methods of resolution
Document: U4.52.14

Operator MODE_STATIQUE

1 Goal

To calculate static modes for a displacement, a force or a unit acceleration imposed.

A static mode is the static deformation of an isostatic or hyperstatic structure to which one
impose:

·
in a ddl blocked (node - component) a unit imposed displacement,
·
in a free ddl (node - component) a unit nodal force,
·
in a ddl (node - component) a unit imposed acceleration,
·
in a direction, a unit imposed acceleration.

The operator allows to calculate the whole of the static modes corresponding to several couples
node - component. The matrix of rigidity must be assembled by using a whole of conditions
with the limits sufficient kinematics so that all the solid modes of body are removed
(operators AFFE_CHAR_MECA [U4.44.01] or AFFE_CHAR_CINE [U4.44.03]). It is possible of
to ask that part of the static modes corresponding to these conditions kinematics.

The produced concept can be used to supplement a modal base of clean modes of vibration
(operator DEFI_BASE_MODALE [U4.64.02] or DYNA_ALEA_MODAL [U4.53.22]) or to determine
loadings necessary to the calculation of the movement of drive under a seismic excitation
(operator CALC_CHAR_SEISME [U4.63.01]).

Product a concept of the mode_stat_depl type, mode_stat_acce or mode_stat_forc according to
the selected option of calculation.
Handbook of Utilization
U4.5- booklet: Methods of resolution
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MODE_STATIQUE

Date
:
01/02/05
Author (S):
Y. PONS, J. PIGAT Key
:
U4.52.14-G Page
: 2/6

2 Syntax
R [mode_stat_xxx] = MODE_STATIQUE


(
MATR_RIGI
=
rigi [matr_asse_DEPL_R]



MATR_MASS
=
mass
[matr_asse_DEPL_R]


/MODE_STAT
=_F (
/TOUT =
“OUI”
/
NOEUD
=



noeu
[l_Kn]
/
GROUP_NO
=
g_noeu [l_Kn]










/TOUT_CMP = “YES”
/
AVEC_CMP
=
l_cmp
[l_Kn]
/
SANS_CMP
=
l_cmp
[l_Kn]








)
/
FORCE_NODALE
=_F (
/ALL = “YES”
/
NOEUD
=



noeu
[l_noeud]
/
GROUP_NO
=
g_noeu [l_gr_noeud]










/TOUT_CMP = “YES”
/
AVEC_CMP
=
l_cmp
[l_Kn]
/
SANS_CMP
=
l_cmp
[l_Kn]









)

/
PSEUDO_MODE
=_F (
/AXE
= I “X”














I “Y”














I “Z”










/DIRECTION
= to l_dir [l_R]











NOM_DIR
= to n_dir
[l_Kn]



















//TOUT =
“OUI”
/
NOEUD
=
noeu
[l_noeud]
/
GROUP_NO
=
g_noeu [l_gr_noeud]










/TOUT_CMP = “YES”



/
AVEC_CMP
=
l_cmp
[l_Kn]
/
SANS_CMP
=
l_cmp
[l_Kn]








)


TITER
= title
[l_Kn]












INFO
=
/
1
[DEFAUT]








/2


);

xxx = depl if the option of calculation is MODE_STAT
= acce if the option of calculation is PSEUDO_MODE
= forc if the option of calculation is FORCE_NODALE
Handbook of Utilization
U4.5- booklet: Methods of resolution
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MODE_STATIQUE

Date
:
01/02/05
Author (S):
Y. PONS, J. PIGAT Key
:
U4.52.14-G Page
: 3/6

3 Operands

3.1 Operand
MATR_RIGI

MATR_RIGI
= rigi

Stamp rigidity of the isostatic or hyperstatic structure.

3.2 Operand
MATR_MASS

MATR_MASS = mass

Stamp of mass of the isostatic or hyperstatic structure.

3.3
Nature of the stresses applied

3.3.1 Word
key
MODE_STAT

/MODE_STAT

Key word factor for the definition of the static modes with imposed displacement.

3.3.1.1 Operands
ALL/NODE/GROUP_NO


/ALL = “YES”

Calculation of the modes on all the nodes of the system which have blocked ddl.



/
NOEUD = noeu

Calculation of the modes on all the nodes noeu (subset of the blocked nodes).



/
GROUP_NO = g_noeu

Calculation of the modes on the groups of nodes g_noeu (subset of the nodes
blocked).

3.3.1.2 Operands
TOUT_CMP/AVEC_CMP/SANS_CMP


/TOUT_CMP = “YES”

Calculation of the modes on all the components blocked with the definite nodes
previously.



/
AVEC_CMP = l_cmp

Calculation of the modes on the components only quoted.



/
SANS_CMP = l_cmp

Calculation of the modes by excluding the quoted components.
Handbook of Utilization
U4.5- booklet: Methods of resolution
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MODE_STATIQUE

Date
:
01/02/05
Author (S):
Y. PONS, J. PIGAT Key
:
U4.52.14-G Page
: 4/6

3.3.2 Word
key
FORCE_NODALE

/
FORCE_NODALE

Key word factor for the definition of the static modes with imposed force.

3.3.2.1 Operand
ALL/NODE/GROUP_NO


/ALL = “YES”

Calculation of the modes on all the nodes of the system which have free ddl.



/
NOEUD = noeu

Calculation of the modes on all the nodes noeu.



/
GROUP_NO = g_noeu

Calculation of the modes on the groups of nodes g_noeu.

3.3.2.2 Operands
TOUT_CMP/AVEC_CMP/SANS_CMP


/TOUT_CMP = “YES”

Calculation of the modes on all the free components with the nodes defined previously.



/
AVEC_CMP = l_cmp

Calculation of the modes on the components only quoted.



/
SANS_CMP = l_cmp

Calculation of the modes by excluding the quoted components.

3.3.3 Word
key
PSEUDO_MODE

/PSEUDO_MODE
Key word factor for the definition of the static modes with imposed acceleration.

3.3.3.1 Operands
CENTER/DIRECTION/NOM_DIR


/AXE = l_axe

Calculate modes along the axes of the total reference mark given (l_axe), these axes being
“X”, “Y” and “Z”.



/DIRECTION = to l_dir

Calculate the mode according to the direction given (to l_dir)
(to l_dir): directing vector with 3 components.




NOM_DIR = to n_dir

Name user which one wishes to give to the mode calculated in the direction (to n_dir).
By defect the name is DIR_N, NR being the number of the static mode.
Handbook of Utilization
U4.5- booklet: Methods of resolution
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MODE_STATIQUE

Date
:
01/02/05
Author (S):
Y. PONS, J. PIGAT Key
:
U4.52.14-G Page
: 5/6

3.3.3.2 Operands
ALL/NODE/GROUP_NO


/
/ALL = “YES”

Calculation of the modes on all the nodes of the system.

/
NOEUD
=
noeu

Calculation of the modes on all the nodes noeu.

/
GROUP_NO
=
g_noeu

Calculation of the modes on the groups of nodes g_noeud.

3.3.3.3 Operands
TOUT_CMP/AVEC_CMP/SANS_CMP



/TOUT_CMP = “YES”

Calculation of the modes on all the components with the nodes defined previously.

/
AVEC_CMP
=
l_cmp

Calculation of the modes on the components only quoted.

/
SANS_CMP
=
l_cmp

Calculation of the modes by excluding the quoted components.

3.4 Operand
TITER


TITER = title

Attache with the concept produced by this operator [U4.03.01].

3.5 Operand
INFO


INFO

Indicate the level of impression of information on file “MESSAGE”:

1: no impression
2: impression of the calculated static modes.
Handbook of Utilization
U4.5- booklet: Methods of resolution
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MODE_STATIQUE

Date
:
01/02/05
Author (S):
Y. PONS, J. PIGAT Key
:
U4.52.14-G Page
: 6/6

4 Phase
of execution

·
for option MODE_STAT or PSEUDO_MODE (on groups of nodes), the operator checks that
the couple node - component is well a blocked ddl,

·
for option FORCE_NODALE, the operator checks that the couple node - component is a ddl
free,

·
for option PSEUDO_MODE (on a direction), the operator normalizes the directing vector given
under key word DIRECTION,

·
the matrix of mass is necessary for the calculation of options PSEUDO_MODE,

·
if a couple node - component appears more once, one makes calculation required only one
only time.

5 Examples
5.1 Calculation of the static modes in unit constant acceleration in
3 directions

% calculation of the static modes in unit constant acceleration in the 3 directions.

1
mode_ I =
-
K (Mr. Ui) with K: stamp rigidity
M m
: atrice of mass

Ui unit vector in direction I
:


mstat = MODE_STATIQUE (MATR_RIGI = rigidity,
MATR_MASS
=
mass,
PSEUDO_MODE=_F (AXE= (“X”, “Y”, “Z”),),








);

5.2
Calculation of the static modes in unit imposed displacement

% calculation of the static modes in unit imposed displacement.

- 1




mode = K
VI
with
K: stamp rigidity


VI
:
vector being worth 1. for the components DX and DY

group of nodes bases.


mstat = MODE_STATIQUE (

MATR_RIGI = rigidity,
MODE_STAT
=_F (
GROUP_NO
=
“bases”,
(
AVEC_CMP
= (
“DX”, “DY”),),








);
Handbook of Utilization
U4.5- booklet: Methods of resolution
HT-66/05/004/A

Outline document