1. Reference problem#

_images/Shape1.gif

1.1. Geometry#

Cube geometry:

Center \(O(0.\mathrm{,0}\mathrm{.}\mathrm{,0}\mathrm{.})\)

Point \(A(0.5\mathrm{,0}.5\mathrm{,0}.5)\)

Side cube \(1m\)

1.2. Material properties#

      • Elastic

        • \(E=5800.0\mathrm{E6}\mathrm{Pa}\) Young’s module

        • \(\rho =2500{\mathrm{kg.m}}^{-3}\) Density

        • \(\nu =0.3\) Poisson’s ratio

      • DRUCK_PRAGER with linear negative work hardening

        • \(\alpha =0.33\) Pressure Dependence Coefficient

        • \({p}_{\mathrm{ultm}}=0.01\) Ultimate cumulative plastic deformation

        • \({\sigma }^{Y}=2.57\mathrm{E6}\mathrm{Pa}\) Plastic constraint

        • \(h=-2.00\mathrm{E8}\mathrm{Pa}\) Work hardening module

      • DRUCK_PRAGER with parabolic negative work hardening

        • \(\mathrm{\alpha }=0.33\) Pressure Dependence Coefficient

        • \({p}_{\mathit{ultm}}=0.01\) Ultimate cumulative plastic deformation

        • \({\mathrm{\sigma }}^{Y}=2.57E6\mathit{Pa}\) Plastic constraint

        • \({\mathrm{\sigma }}_{\mathit{ultm}}^{Y}=0.57E6\mathit{Pa}\) Ultimate constraint

      • DRUCK_PRAG_N_A with parabolic negative work hardening

        • \(\alpha =0.33\) Pressure Dependence Coefficient

        • \({p}_{\mathrm{ultm}}=0.01\) Ultimate cumulative plastic deformation

        • \({\sigma }^{Y}=2.57\mathrm{E6}\mathrm{Pa}\) Plastic constraint

        • \({\sigma }_{\mathrm{ultm}}^{Y}=0.57\mathrm{E6}\mathrm{Pa}\) Ultimate constraint

        • \(\mathrm{\beta }=0.33\) Initial expansion coefficient

      • Hydraulic behavior: saturated liquid

        • \(\mathrm{Pre1}=1\mathrm{Pa}\) Reference liquid pressure

        • \({\rho }_{\mathrm{pre1}}=1000{\mathrm{kg.m}}^{-3}\) Density of water

        • \(\mathrm{Poro}=0.14\) Initial porosity

        • \({\rho }_{\mathrm{vh}}=2400{\mathrm{kg.m}}^{-3}\) Homogenized density

        • \(\mathrm{bio}=1\) Biot coefficient

        • \({K}_{\mathrm{intrinsèque}}=1E-18{m}^{2}\) Intrinsic permeability

        • \(\frac{1}{{K}_{l}}=0\) Incompressible liquid

        • \(\mathrm{vi}=1.0E-3\mathrm{Pa.s}\) Viscosity

1.3. Boundary conditions and loads#

Boundary conditions and loads are applied in two steps:

  • Step \(A\): \(t\in [\mathrm{0,1}\mathrm{.}]\)

Boundary conditions

    • Knot pressure \(\mathrm{PRE1}=0.\)

    • Imposed movements, of symmetry, on the faces of the cube belonging to the planes

\(X=-0.5\) \(\mathrm{DX}=0\)

\(Y=-0.5\) \(\mathrm{DY}=0\)

\(Z=-0.5\) \(\mathrm{DZ}=0\)

Loading

    • We progressively apply \(p={2.10}^{6}\mathrm{Pa}\) compression to the faces of the cube belonging to the planes: \(X=0.5\), \(Y=0.5\) and \(Z=0.5\)

_images/Shape2.gif
      • Step B: \(t\in \text{]}\mathrm{1,2}\mathrm{.}\text{]}\)

From the state of constraints obtained at instant \(t=1.s\), the following conditions are applied to the faces of the cube:

Movations

    • For the face belonging to plane \(Z=0.5\), the \(\mathrm{DZ}\) displacement is gradually applied, following a ramp:

_images/Shape3.gif
    • For faces belonging to planes \(X=-0.5,Y=-0.5,Z=-0.5\), symmetry conditions are applied.

Loads: the loads applied are constant:

        • Face belonging to plane \(X=0.5\) \(p={2.10}^{6}\mathrm{Pa}\)

        • Face belonging to plane \(Z=0.5\) \(p={2.10}^{6}\mathrm{Pa}\)