Reference problem
=====================


Geometry
---------

The geometry is chosen deliberately simple, to translate a state of stress and homogeneous deformation, as is the case in uniaxial creep. This is a volume element represented by a cube with side :math:`3\mathrm{mm}`. The modeling is solid and the creep takes place under imposed stress.


Material properties
----------------------

The characteristics are as follows:

Keyword ELAS:


* :math:`\mathit{YOUNG}\mathrm{=}150000.0\mathit{MPa}`


* :math:`\mathrm{NU}=0.30`

Keyword VENDOCHAB:


* :math:`{S}_{\mathrm{VP}}=0.`


* :math:`\mathrm{SEDVP1}=0.`


* :math:`\mathrm{SEDVP2}=0.`


* :math:`{N}_{\mathrm{VP}}=12.`


* :math:`{M}_{\mathrm{VP}}=9.`


* :math:`{K}_{\mathrm{VP}}=2110.`


* :math:`{A}_{D}=3191.`


* :math:`{R}_{D}=6.3`


* :math:`{K}_{D}=14`


Boundary conditions and loads
-------------------------------------

:math:`\mathrm{DZ}=0` on the bottom side (:math:`Z=0`)

:math:`\mathrm{DY}=0` on the left side (:math:`Y=0`)

:math:`\mathrm{DX}=0` on the back side (:math:`X=0`)

Pressure of :math:`200\mathrm{MPa}` imposed on the upper surface, such as:

:math:`P=0` to :math:`t=\mathrm{0s}`

:math:`P=200\mathrm{MPa}` to :math:`t=\mathrm{0.1s}`

:math:`P=200\mathrm{MPa}` to :math:`t\mathrm{=}2.5{10}^{6}s`

This corresponds to a uniaxial creep test under a constant loading of :math:`200\mathit{MPa}`.


Initial conditions
--------------------

Zero stresses and deformations.