/FAIL/FABRIC

Block Format Keyword Describes an anisotropic strain failure model for fibers of fabric material.

Format

(1)	(3)	(5)	(7)
/FAIL/FABRIC/`mat_ID`/`unit_ID`
$ε_{f 1}$	$ε_{r 1}$	$ε_{f 2}$	$ε_{r 2}$
`fct_ID`

Optional Line

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
`fail_ID`

Definitions

Field	Contents	SI Unit Example
`mat_ID`	Material identifier (Integer, maximum 10 digits)
`unit_ID`	Unit Identifier (Integer, maximum 10 digits)
$ε_{f 1}$	Failure tensile strain in direction 1. Default = 1.0E20 (Real)
$ε_{r 1}$	Rupture tensile strain in direction 1. Default = 2.0E20 (Real)
$ε_{f 2}$	Failure tensile strain in direction 2. Default = 1.0E20 (Real)
$ε_{r 2}$	Rupture tensile strain in direction 2. Default = 2.0E20 (Real)
`fct_ID`	Function identifier of $f (\dot{ε})$ . It is function of scale factor for tensile strain limits in both direction vs. corresponding strain rates. (Integer)
`fail_ID`	Failure criteria identifier. (Integer, maximum 10 digits)

Example (Fabric)

#RADIOSS STARTER
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/UNIT/1
unit for mat
                  kg                  mm                  ms
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#-  2. MATERIALS:
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/LAW58/1/1
Altair test fabric LAW58
#              RHO_I
               8e-07
#                 E1                  B1                  E2                  B2                FLEX
                0.38                   0                0.38                   0                   1
#                 G0                  GT              AlphaT                 Gsh           sensor_ID
              0.0035              0.0055               7.175                   0                   1
#                 Df                  Ds               GFROT                             ZERO_STRESS
                0.00                0.00                   0                                       1	 
#       N1        N2                  S1                  S2               FLEX1               FLEX2
         1         1                   0                   0                   0                   0
#  fct_ID1                       Fscale1
       500                             1
#  fct_ID2                       Fscale2
       501                          1.07
#  fct_ID3                       Fscale3
       502                             1
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#  FCT_ID4   FCT_ID5             Fscale4             Fscale5   FCT_ID6             Fscale6
       600       600                   1                   1       502                   1
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/FAIL/FABRIC/1/1
#             EPS_f1              EPS_r1              EPS_f1              EPS_r1
                0.2                  0.5                 0.2                 0.5
#    Fct_ID
         0		 
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/FUNCT/500
stress-strain curve dir 1
#        true strain         true stress
            0.0e+000                   0
            1.0e-002         2.9343e-003
            2.0e-002         5.2630e-003
            3.0e-002         6.9235e-003
            4.0e-002         8.4176e-003
            5.0e-002         1.0120e-002
            6.0e-002         1.2102e-002
            7.0e-002         1.4219e-002
            8.0e-002         1.6595e-002
            9.0e-002         1.9202e-002
            1.0e-001         2.2040e-002
            1.1e-001         2.5270e-002
            1.2e-001         2.8711e-002
            1.3e-001         3.2558e-002
            1.4e-001         3.6676e-002
            1.5e-001         4.1031e-002
            1.6e-001         4.5697e-002
/FUNCT/501
stress-strain curve dir 2
#        true strain         true stress
            0.0e+000                   0
            1.0e-002         3.7475e-003
            2.0e-002         6.4746e-003
            3.0e-002         8.6433e-003
            4.0e-002         1.0769e-002
            5.0e-002         1.2923e-002
            6.0e-002         1.5325e-002
            7.0e-002         1.8090e-002
            8.0e-002         2.1231e-002
            9.0e-002         2.4870e-002
            1.0e-001         2.8884e-002
            1.1e-001         3.3246e-002
            1.2e-001         3.8027e-002
            1.3e-001         4.3127e-002
            1.4e-001         4.8519e-002
            1.5e-001         5.4217e-002
            1.6e-001         6.0077e-002
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/FUNCT/502
stress-strain curve dir 12
#              angle         true stress
  -16.170000000e-000  -1.5741500000e-003
  -7.1750000000e-000  -4.3750000000e-004
   0.0000000000e+000   0.0000000000e+000
   7.1750000000e-000   4.3750000000e-004
   16.170000000e-000   1.5741500000e-003
/FUNCT/600
unloading stress-strain curve dir 1, 2
#                  X                   Y
            0.0e+000            0.0e+000
            2.0e-002            5.0e-004
            4.0e-002            1.0e-003
            6.0e-002            2.0e-003
            8.0e-002            5.0e-003
            1.0e-001            1.0e-002
            1.2e-001            3.0e-002
            1.4e-001            7.0e-002
#ENDDATA
/END
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

Comments

The failure criteria is only compatible with fabric material /MAT/LAW58 (FABR_A).
Failure and damage is defined independently in each direction ( $i$ =1,2), if:(1)
$ε_{i} \geq ε_{f i} \Rightarrow D_{i} = \frac{ε_{i} - ε_{f i}}{ε_{r i} - ε_{f i}}$

Where, $ε_{i}$ is the fiber tensile strain.

The fiber stress will be reduced by:(2)
$σ_{i} = σ_{i} \cdot (1 - D_{i})$
Element deletion could also be controlled by P_thickfail in /PROP/TYPE16.
The fail_ID is used with /STATE/SHELL/FAIL and /INISHE/FAIL. There is no default value. If the line is blank, no value will be output for failure model variables in the /INISHE/FAIL (written in .sta file with /STATE/SHELL/FAIL option).
Element will be deleted only if damage values in both directions reach limit values D= 1.0 in all integration points. Maximum damage value D can be observed by using /ANIM/SHELL/DAMA and /H3D/SHELL/DAMA/NPT=ALL in Engine.