*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`	$ρ_{L}$	`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`

Field	Contents	SI Unit Example
`mat_ID`mat_ID	Material identifier. (Integer)
$ρ_{L}$	Mass per unit length. (Real)	$[\frac{kg}{m}]$
`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)	$[\frac{N}{m^{2}}]$
`A`	Cross-sectional area for bending/compression stiffness. (Real)	$[m^{2}]$
`I`	Area moment of inertia. (Real)	$[m^{4}]$
`J`	Polar moment of inertia. (Real)	$[m^{4}]$
`AS`	Shear area. (Real)	$[m^{2}]$
`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)	$[\frac{N}{m^{2}}]$
`TC`	Coating thickness.	$[m]$
`E22`	(Optional) Elastic modulus in transverse direction. 3	$[\frac{N}{m^{2}}]$
`NU12`	(Optional) Poisson number. 3
`G12`	(Optional) Shear modulus. 3

This keyword maps to /MAT/LAW114 (SPR_SEATBELT) for 1D seatbelts and /MAT/LAW119 (SH_SEATBELT) for 2D seatbelts.
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.
Default value of shell elastic modulus E22 is 10% of the spring stiffness; Longitudinal stiffness of the shells is 1% of the spring stiffness.
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.