/PROP/TYPE16 (SH_FABR)

Block Format Keyword This property set is used to define the anisotropic layered shell property set. This property is currently only compatible with Elastic Anisotropic Fabric (/MAT/LAW58 (FABR_A)).

Format

(1)	(2)	(3)	(5)	(7)	(8)	(9)
/PROP/TYPE16/`prop_ID`/`unit_ID` or /PROP/SH_FABR/`prop_ID`/`unit_ID`
`prop_title`
`I`_shell	`I`_smstr	`I`_sh3n		`P_thick`_fail
`h`_m		`h`_f	`h`_r	`d`_m
`N`	`I`_strain	`Thick`	`A`_shear		`I`_thick
`V`_X		`V`_Y	`V`_Z	`Skew_ID`	`I`_pos
$ϕ_{i}$		$α_{1}$	`t`_i	`Z`_i		`mat_ID`_i

Each layer (integration point) per line:

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
$ϕ_{i}$		$α_{1}$		`t`_i		`Z`_i		`mat_ID`_i

Definitions

Field	Contents	SI Unit Example
`prop_ID`	Property identifier (Integer, maximum 10 digits)
`unit_ID`	Unit Identifier (Integer, maximum 10 digits)
`prop_title`	Property title (Character, maximum 100 characters)
`I`_shell	Shell element formulation flag. = 0 Use value in /DEF_SHELL. = 1 Default, if /DEF_SHELL is not defined Q4, visco-elastic hourglass modes orthogonal to deformation and rigid modes (Belytschko). = 2 Q4, visco-elastic hourglass without orthogonality (Hallquist). = 3 Q4, elasto-plastic hourglass with orthogonality. = 4 Q4 with improved type 1 formulation (orthogonalization for warped elements). = 12 QBAT shell formulation. = 24 QEPH shell formulation. (Integer)
`I`_smstr	Shell small strain formulation flag. = 4 (Default) Full geometric nonlinearities (in Radioss Engine, option /DT/SHELL/CST has no effect). (Integer)
`I`_sh3n	3 node shell element formulation flag. = 0 Use value in /DEF_SHELL. = 1 Standard triangle (C0). = 2 Default, if /DEF_SHELL is not defined Standard triangle (C0) with modification for large rotation. = 30 DKT18 = 31 DKT_S3 (Integer)
`P_thick`_fail	Element suppression criterion. It is ratio of the sum of failed integration points thickness over total shell thickness necessary to delete the element. 7 This option used for /FAIL/FABRIC. $0.0 \leq P_t h i c k_{f a i l} \leq 1.0$ (Real)
`h`_m	Shell membrane hourglass coefficient. Only used when `I`_shell=1, 2, 3, 4. Default = 0.01 Default = 0.1 for `I`_shell =3 (Real)
`h`_f	Shell out-of-plane hourglass. Only used when `I`_shell=1, 2, 3, 4. Default = 0.01 (Real)
`h`_r	Shell rotation hourglass coefficient. Only used when `I`_shell=1, 2, 3, 4. Default = 0.01 Default = 0.1 for `I`_shell =3 (Real)
`d`_m	Shell membrane damping. It is used for Material LAW58. Default =0.075 for `I`_shell ≠12 Default =0.2 for `I`_shell =12 Default = 0.0 for all 3 node shells (Real)
`N`	Number of layers, with $1 \leq N \leq 100$ . 6 Default = 1 (Integer)
`I`_strain	Compute strains for post-processing flag. = 0 Use value in /DEF_SHELL. = 1 Default, if /DEF_SHELL is not defined Yes = 2 No (Integer)
`Thick`	Shell thickness. (Real)	$[m]$
`A`_shear	Shear factor Default is Reissner value: 5/6 (Real)
`I`_thick	Shell resultant stresses calculation flag. = 0 Use value in /DEF_SHELL. = 1 Thickness change is taken into account. = 2 Default, if /DEF_SHELL is not defined Thickness is constant . (Integer)
`V`_X	X component for reference vector. 3 Default = 1.0 (Real)
`V`_Y	Y component for reference vector. Default = 0.0 (Real)
`V`_Z	Z component for reference vector. Default = 0.0 (Real)
`Skew_ID`	Skew identifier for reference vector. 3 If the local skew is defined, its X-axis replaces the global vector V. `V`_X, `V`_Y, and `V`_Z coordinates are ignored. Default = 0 (Integer)
`I`_pos	Layer positioning flag for reference vector. 4 = 0 (Default) Layer positions `Z`_i are automatically calculated with regard to layer thicknesses. = 1 All layer positions `Z`_i must be user-defined. Default = 0 (Integer)
$ϕ_{i}$	Angle $ϕ_{i}$ of 1st local axis for layer `i`. 3 (Real)	$[\deg]$
$α_{1}$	Angle between first and second axis. 3 Default = 90.0 (Real)	$[\deg]$
`t`_i	Thickness `t`_i of layer `i`. (Real)	$[m]$
`Z`_i	Z position of layer i (`Z`_i defines the position of the middle of the layer). Default = 0.0 (Real)	$[m]$
`mat_ID`_i	Material identifier for layer `i`. Same material should be used for all layers. (Integer)

Example

#RADIOSS STARTER
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#-  1. LOCAL_UNIT_SYSTEM:
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/UNIT/2
unit for PROP
#              MUNIT               LUNIT               TUNIT
                  Mg                  mm                   s
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#-  2. GEOMETRICAL SETS:
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/PROP/TYPE16/2/2
prop type 16
#   Ishell    Ismstr     Ish3n
         0         0         0
#                 hm                  hf                  hr                  dm
                   0                   0                   0                   0
#        N   Istrain               Thick              Ashear              Ithick
         3         0                 1.6                   0                   0
#                 Vx                  Vy                  Vz   skew_ID      Ipos
                   1                   0                   1         0         0
#                Phi               Alpha                  Ti                  Zi   mat_IDi
                  45                  90                  .5                             1          
                  90                  90                  .6                             2          
                 -45                  90                  .5                             1          
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

Comments

I_shell – 4-node shell formulation flag
The hourglass formulation is visco-elastic for Q4 shells (I_shell=1,2,3,4).
h_m, h_f, and h_r - Hourglass coefficients
- h_m, h_f, and h_r are used only for Q4 shells (I_shell=4). They must have a value between 0 and 0.05.
- For I_shell=3, default values of h_m and h_r are 0.1 with larger values possible.
Anisotropy in local coordinate system
Two different ways to define the anisotropy with this property

Skew_ID=0

Anisotropic direction defined with global vector V (components defined in Line 6) and angle $ϕ_{i}$ (angle in degree) for each layer.

Skew_ID≠0

Anisotropic direction defined with skew (X-axis in skew replaces the global vector $V$ ) and angle $ϕ_{i}$ (angle in degree) for each layer.

For both ways (with vector $V$ or with skew), Projection of vector $V$ (or x-axis of skew) on shell element plane becomes the vector $V^{'}$ . Then for each layer, the anisotropic direction.
(direction 1) is vector $V^{'}$ turned $ϕ_{i}$ degrees, where the positive direction is based on the shell normal $n$ .

Figure 1.
- $α_{i}$ is the angle between local anisotropic direction 1 and 2 (directions of anisotropy) for layer i. If $α_{i} = 90^{\circ}$ , then layer is in orthotropic.
- In case of reference metrics, the orientation for directions of anisotropy must be defined with the reference geometry, not the initial one.
I_pos – Layer position
I_pos= 0: layer positions are calculated automatically.
If (1)
$T h i c k \neq \sum_{i}^{N} t_{i}$
- A warning message is displayed
- Individual layer thickness will be adjusted to new layer thickness $t_{i}^{n e w}$ with:(2)
  $T h i c k = \sum_{i}^{N} t_{i}^{n e w}$
  
  Here "Thick" and $t_{i}$ are the shell thickness and layer thickness which specified in input.
  
  Figure 2.
- I_pos = 1: all layer positions in the element thickness are user defined (with $t_{i}$ and $Z_{i}$ ).
  - “Thick” is not checked, as it does not need to be equal to the sum of layer thickness.
  - Multiple layers are allowed to have the same space position.
For more details, refer to Layer thickness and position calculation in FAQs.
The material law number given in /PART will be used to define the density and Young’s Modulus which then is used to calculate the time step and interface stiffness.
Each i layer has only 1 integration point through its thickness.
Option P_thick_fail is used by /FAIL/FABRIC criterion. This is the only criterion which is compatible with /PROP/TYPE16 and /MAT/LAW58.