6. D modeling#

6.1. Characteristics of modeling#

Modeling POU_D_TGM (SEG2)

Number of knots: 11

Number of meshes and type: 10 SEG2 evenly distributed in length

Number of fibers: 50 (5 in the width and 10 in the thickness)

Number of meshes and type: 50 QUA4

The calculation strategy used is divided into two steps:

- - Imposed load: The structure was pre-deformed according to its first buckling mode and with a very low amplitude compared to the length of the beam (in the order of \({5.10}^{\mathrm{-}4}m\)). Charging is applied up to \(P\mathrm{/}{P}_{\mathit{cr}}\mathrm{=}0.95\).
  - Imposed displacement: clear of 0.95, the structure begins to undergo a strong lateral displacement for a very small increase in load, so the structure is controlled in arc length to determine the post-buckling behavior.
  - The results are in good agreement with the reference solution starting from ETA_PILOTAGE = 1.152. Before this value, pre-deformation (necessary to obtain buckling) degrades the solution, and the differences with analytical solutions are significant (up to 60%). The corresponding values are subject to non-regression tests. But this difference is only linked to the initial (arbitrary) pre-deformation, since by increasing the vertical loading, we find the right solution.