strange moment

[Anonymous]

hi guys,

I have a slab one-way structure, where the steel beam support the slab, but I think, I get a strange moment for the beams that shown in attached picture. I think the shown beams should have a bigger than the edge beam, but it looks on the contrary. I have also attached the model. Any help appreciated. 

[Rafal.Gaweda]

Your expectations are correct if you, for example, consider all beams of the same section (the same stiffeness)

 

[t.sautierr]

in addtition to Rafal's comment, it is linked to the relative rigidity of the different element (pannels and bars).

See this model, load case 2, I change the rigidity of your slab to something like bubble gum -> tha slab behaves like cladding (that i put instead of pannels in the copied structure)

Actually in your model central bars is much less rigid than side bars -> the slab transfer some loads "from the middle" directly to the side beams as the central beam is quite flexible compared to the slab.