Lower level columns taking smaller loads?

[Anonymous]

I am modeling a simple frame structure with cross- bracing elements.

When I look at the results for compression force acting on the columns, some of the lower columns are taking less load then the ones above them.

From what I can understand, the cross-bracing seems to be taking loads in the z (gravity) direction. I have tried to release the bracing from z (xxfxxf) but it still seems to be taking some sort of load off the columns.

When i define the braces as tension only element, non-linear solutions are required and therefore I cannot perform an analysis with automatic load combos.

How should columns and cross-braces be modeled to avoid having cross bracing take Z (gravity) loads.

Thanks,

Nick

[mustafahesenow]

Hi @Anonymous

Can you send us the model please.

[t.sautierr]

You can define gap in your bracket in order to allow for some displacement before it stats resisting.
But normally if your cross-bracing is in proportion to the column, the stiffness difference shall make the job and the X will not be over-loaded compared to the column.