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Structural model from beam bending stiffness distribution

Structural model from beam bending stiffness distribution

Structural model from beam bending stiffness distribution

Hi all,

I have a nonlinear beam from which I know the distribution of bending and torsional stiffness, but nothing about the distribution of cross sectional area, area moment of inertia and material property. The format is more or less the following (values are just for example):

t EIcc GJ
0.00000 3.60000 2.25000
0.25000 3.58500 2.15000
0.80000 3.52909 2.00000
1.00000 3.51217 1.52230
1.50000 3.41108 0.77042
2.00000 3.21321 0.65660
2.50000 2.92874 0.66845
3.00000 2.57549 0.73801
3.50000 2.18254 0.82372
4.00000 1.78191 0.86059

where the t entry constitutes the 1D coordinate of the beam. Each t corresponds to a position in a xyz grid defined separately. EIcc is the bending stiffness (the beam should represent the structure of a wing, so "cc" means around the axis coincident with the local chord) and GJ is the torsional stiffness.

I would like to build a Nastran model out of this data. I know I cannot use any CBAR or CBEAM element because I do not have any geometrical and material info of the beam. From a research on the internet and on Nastran manuals I have seen that I could try to use cards like DMIG and GENEL. My question is: is there any more immediate method to use this kind of data to build a structural model in Nastran?

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