4. C modeling#

4.1. Characteristics of modeling#

C modeling is performed on a hardware point, using SIMU_POINT_MAT.

The axial deformation imposed during the isotropic compression phase is equal to \(-{\mathrm{\sigma }}_{0}/3K\) (axial deformation making it possible to reach \({\mathrm{\sigma }}_{\mathit{zz}}={\mathrm{\sigma }}_{0}\), applied in \(t=1s\)). During the same time interval, lateral constraints change from \({\mathrm{\sigma }}_{\mathit{xx}}={\mathrm{\sigma }}_{\mathit{yy}}=0\) to \({\mathrm{\sigma }}_{\mathit{xx}}={\mathrm{\sigma }}_{\mathit{yy}}={\mathrm{\sigma }}_{0}\). The maximum axial deformation applied during the deviatoric phase is \({\mathrm{ϵ}}_{\mathit{zz}}=-0.03\text{\%}\) (final instant \(t=30s\)). During the deviatoric phase, the lateral stresses are kept constant, equal to \({\mathrm{\sigma }}_{\mathit{xx}}={\mathrm{\sigma }}_{\mathit{yy}}={\mathrm{\sigma }}_{0}\).

4.2. Tested sizes and results#

4.2.1. Tested values#

Five non-regression tests are carried out at the end of the test at \(t=30s\), on:

  • SIXX — lateral constraint that must be equal to the imposed lockdown, i.e. \({\mathrm{\sigma }}_{0}\);

  • SIZZ — constraint resulting from the law of behavior;

  • V7— plastic multiplier (equal to the equivalent plastic deformation of Von-Mises);

  • V8— plastic volume deformation (\({\mathrm{ϵ}}_{\mathit{kk}}-{\mathrm{ϵ}}_{\mathit{kk}}^{e}\));

  • V9— dissipation (\(\int {\mathrm{\sigma }}_{\mathit{ij}}\left(\mathrm{\delta }{\mathrm{ϵ}}_{\mathit{ji}}-\mathrm{\delta }{\mathrm{ϵ}}_{\mathit{ji}}^{e}\right)\)).

\(t=30\mathit{sec}\)

Analytical solution from modeling A

Calculated solution from modeling C

SIZZ (Pa)

\(-173289.5416041\)

\(-173077.28029053428\)

SIXX (Pa)

\(-50000.\)

\(-50000.00000615134\)

V8

\(0.00016784502547224\)

\(0.00011457113677334\)

V7

\(0.00033099447556585\)

\(0.0002523646130019748\)

V9 (Pa)

\(2.7623234303334216\)

Table 4.2.1-1: Validation of results for modeling C

It is normal to notice some differences with the analytical solution for components SIZZ, V7, and V8 since the smoothed criterion used by the Mohr-Coulombas law deviates somewhat from the original Mohr-Coulomb criterion.