1. Reference issues#
1.1. Geometry#
Geometry is a segment with 2 nodes. The initial length of the segment is \(0.1\mathrm{m}\).
1.2. Modeling A#
Discreet is a SEG2de type K_T_D_L. Its behavior is CHOC_ENDO.
1.2.1. Material properties#
The table below shows the characteristics of the material. During a calculation carried out with the operator STAT_NON_LINE, depreciation is not taken into account.
Ux [m] |
Strength [N] |
Stiffness [N/m] |
0.00 |
0.0 |
2000.0 |
0.20 |
400.0 |
2000.0 |
0.50 |
450.0 |
2000.0 |
0.70 |
400.0 |
2000.0 |
0.95 |
375.0 |
2000.0 |
1.30 |
350.0 |
2000.0 |
1.60 |
300.0 |
2000.0 |
The figure below shows the behavior corresponding to the data.
The following commands are used to define the material:
ldepla= nu.Array ([0.0, 2.0, 5.0, 7.0, 9.50, 13.0, 16.0,]) /10.0
lforce= nu.Array ([0.0, 4.0, 4.5, 4.0, 3.75, 3.50, 3.0,]) * 100.0
# Constant stiffness
lraid= nu.Array ([2.0, 2.0, 2.0, 2.0, 2.0, 2.0, 2.0,]) * 1000.0
# Damping: useless in static but mandatory to give
death = nu.Array ([0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,])
#
fctfx = DEFI_FONCTION (NOM_PARA = “X”, ABSCISSE = ldepla, ORDONNEE = lforce, )) **
fctrd = DEFI_FONCTION (NOM_PARA = “X”, ABSCISSE = lrepla, ORDONNEE = stiff, )) **
ctam = DEFI_FONCTION (NOM_PARA = “X”, ABSCISSE = ldepla, ORDONNEE = lamort, )) **
#
Grilleac = DEFI_MATERIAU (
DIS_CHOC_ENDO = _F (
FX = fctfx, RIGI_NOR = fctrd, AMOR_NOR **** = fctam,
DIST_1 = 0.0, DIST_2 ** = 0.0,
CRIT_AMOR = “INCLUS”,
),
)
Note: it is mandatory to fill in CRIT_AMOR. When the calculation is performed in non-linear statics, whether the value is INCLUS or EXCLUS has no influence on the results [R5.03.17].
1.3. B modeling#
This case models behavior CHOC_ENDO with a stiffness that is variable and a function of \(\mathrm{Ux}\).
The discrete one is a K_T_D_L.
1.3.1. Material properties#
The table below shows the characteristics of material DIS_CHOC_ENDO. For a calculation carried out with the operator STAT_NON_LINE, depreciation is not taken into account.
Ux [m] |
Strength [N] |
Stiffness [N/m] |
0.00 |
0.0 |
2000.0 |
0.20 |
400.0 |
2000.0 |
0.50 |
450.0 |
1800.0 |
0.70 |
400.0 |
1400.0 |
0.95 |
375.0 |
1400.0 |
1.30 |
350.0 |
1350.0 |
1.60 |
300.0 |
1330.0 |
Compared to modeling \(A\), only the definition of stiffness changes.
# Variable stiffness
lraid= nu.Array ([2.0, 2.0, 1.8, 1.4, 1.4, 1.35, 1.33,]) * 1000.0
The figure below shows the behavior corresponding to the data.
