4. B modeling#
We note that the girder is very stiff in terms of its traction-compression modes:
\({f}_{0\mathit{traction}/\mathit{compression}}=\frac{1}{2\pi }\sqrt{(a)}=\frac{1}{2\pi }\sqrt{(\frac{E}{\rho })}=806\mathit{Hz}\)
In comparison, the frequency of traction-compression forces at \(\frac{1}{2\pi }\mathit{Hz}\) can be considered to be almost static. This is what is done in modeling B: we compare the results of a calculation with the linear static operator of*Code_Aster* with the results of modeling A on the case of distributed force.
Since finite element modeling is identical to that of modeling A, the expected results are the same:
Load distributed under traction; efforts « » EFGE_ELNO « » ``
Analytical Results |
Tolerance |
||
Normal effort for \(x=0\) |
|
472.478 N |
1E -3% |
\(t=2/3s\) |
392.944 N |
1E -3% |
|
Normal effort for \(x=L/2\) |
|
0 N |
1E-6 N (*) |
\(t=2/3s\) |
0N |
1E-6N (*) |
(*) Absolute difference