MAT_MULTILAYER_ORTHOTROPIC

Material properties

Deprecated command

This command is deprecated and will soon be phased out.

*MAT_MULTILAYER_ORTHOTROPIC
"Optional title"
mid, $\rho$, $E_1$, $E_2$, $G_{12}$, $\nu_{12}$
$E_3$, $G_{13}$, $G_{23}$, $\nu_{13}$, $\nu_{23}$, $\varepsilon_t$, $\varepsilon_c$, erode
ndir, $\alpha_1$, ..., $\alpha_7$
$c$

Parameter definition

Variable
Description
mid
Unique material identification number
$\rho$
Density
$E_1$
In-plane Young's modulus (0-direction)
$E_2$
In-plane Young's modulus (othogonally to 0-direction)
$G_{12}$
In-plane shear modulus
$\nu_{12}$
Poisson's ratio
$E_3$
Young's modulus in transverse direction
$G_{13}$
Transverse shear modulus
$G_{23}$
Transverse shear modulus
$\nu_{13}$
Poisson's ratio
$\nu_{23}$
Poisson's ratio
$\varepsilon_t$
Tensile failure strain in fiber direction
$\varepsilon_c$
Compressive failure strain in fiber direction
erode
Element erosion flag
options:
0 $\rightarrow$ failed elements keep the bulk stiffness
1 $\rightarrow$ failed elements are eroded
2 $\rightarrow$ node splitting
ndir
Number of fiber directions (up to 7)
$\alpha_1$, ..., $\alpha_7$
Fiber directions for failure check (angles relatively the 0-direction)
$c$
Strain rate sensitivity parameter

Description

This is an orthototropic composite model where failure can occur in up to 7 different fiber directions. The stress can be expressed as:

$\boldsymbol{\sigma} = \mathbf{L} : \boldsymbol{\varepsilon} + c \dot{\boldsymbol{\varepsilon}}$

where $\mathbf{L}$ is the tangential stiffness of the material (fourth order tensor). Failure occurs if the tensile or compressive strain in a fiber direction exceeds $\varepsilon_t$ and $\varepsilon_c$, respectively. All deviatoric stresses are set to zero at fiber failure.

Initial fiber directions need to be defined using either INITIAL_MATERIAL_DIRECTION, INITIAL_MATERIAL_DIRECTION_VECTOR or INITIAL_MATERIAL_DIRECTION_WRAP.