*MAT_B01 (SEATBELT)

LS-DYNA Input Interface KeywordDefines a 1D seatbelt material.

Format

(1) (2) (3) (4) (5) (6) (7) (8)
*MAT_B01_{OPTION1} or *MAT_SEATBELT_{OPTION1}
mat_ID ρL fct_load fct_uload Lmin RE E
If E > 0, insert the following line
(1) (2) (3) (4) (5) (6) (7) (8)
A I J AS Fmax Mmax R
If OPTION1=2D, insert the following lines
(1) (2) (3) (4) (5) (6) (7) (8)
EC TC E22 NU12
G12A

Definition

Field Contents SI Unit Example
OPTION
2D
mat_ID Material identifier.

(Integer)

ρL Mass per unit length.

(Real)

[kgm]
fct_load Curve identifier for force versus engineering strain in loading.

(Integer)

fct_uload Curve identifier for force versus engineering strain in unloading.

(Integer)

Lmin Minimum length for elements connected to slipring and retractors.

(Real)

[m]
RE
= 0
No stiffness reduction in compression.
= 1
Stiffness in compression is 1% of tensile stiffness=0,
E Elastic modulus for bending/compression stiffness.

(Real)

[Nm2]
A Cross-sectional area for bending/compression stiffness.

(Real)

[m2]
I Area moment of inertia.

(Real)

[m4]
J Polar moment of inertia.

(Real)

[m4]
AS Shear area.

(Real)

[m2]
Fmax Maximum force in compression/tension.

(Real)

[N]
Mmax Maximum torque.

(Real)

[Nm]
R Rotational mass scaling factor.

(Real)

EC Elastic modulus for coating stiffness. 3

(Real)

[Nm2]
TC Coating thickness. [m]
E22 (Optional) Elastic modulus in transverse direction. 3 [Nm2]
NU12 (Optional) Poisson number. 3
G12 (Optional) Shear modulus. 3

Comments

  1. This keyword maps to /MAT/LAW114 (SPR_SEATBELT) for 1D seatbelts and /MAT/LAW119 (SH_SEATBELT) for 2D seatbelts.
  2. Seatbelt springs are created for 2D seatbelt components according to a skew given in correspondent /PROP/TYPE9 (SH_ORTH). Direction N1, N2 of the skew is the transverse direction of the seatbelt. Spring stiffness is set according to loading and unloading functions.
  3. Default value of shell elastic modulus E22 is 10% of the spring stiffness; Longitudinal stiffness of the shells is 1% of the spring stiffness.
  4. Coating stiffness is activated only when the number of layers in /PROP/TYPE9 (SH_ORTH) is equal to 3. In this case, it is assumed that upper and lower layers are the elastic coating with thickness TC and the middle layer is the seatbelt shell.