Finite element model versus beam theory model

[Kerve89]

Hi,

I have recently developed a both a beam theory model and a finite element model of a bucket wheel reclaimer for different reasons.

I am confident that the beam theory model is accurate and am trying to use the beam theory model to validate the finite element model. The problem I am having is how to compare "apples with apples" as the FEM requires a lot of engineering interpretation.

My thoughts are to calculate bending, shear and axial stresses in the beam theory model and comparing these to the FEM model.

Can anyone advise if there is a better method?

Does anyone no a good way to compare buckling results?

Any help would be awesome.

Cheers

 

[Ron]

Is the main beam a built-up section or is it trussed?

 

[Kerve89]

Hi Ron,

The main section is fully trussed.

 

[racookpe1978]

Why do you suspect the FEA model is incorrect?

Or,asking that the other way, why do the two models differ, and is that difference critical to your design?

(Can you save significant time, money or material choosing one model over the other? If one is wrong, and the other closer to the real world, will you lose significant time, money and material choosing the wrong one?)

 

[rb1957]

"My thoughts are to calculate bending, shear and axial stresses in the beam theory model and comparing these to the FEM model."
sounds like a reasonable approach.

your FEA might allow you to section your model and determine the sum force and moments on the section (something you can compare with the beam model).


another day in paradise, or is paradise one day closer ?

 

[Kerve89]

I don't suspect the FEA model to be incorrect, I just want to prove that it is correct.
The FEA model can be far more useful than the beam model in a maintenance space, you can accurately model damage etc to ascertain changes in load path.

The beam theory model was developed a while ago for a separate project and is being used purely as a control. As soon as I have validated the FEM, the beam theory model is redundant.

 

[rb1957]

a prudent course of action.

you can also compare deflections ... FEM, beam model, real article

another day in paradise, or is paradise one day closer ?