topic Composite Beam in Robot Structural Analysis Forum

Composite Beam

Michele100100 — Thu, 30 Mar 2023 09:54:11 GMT

Hello,

I did a composite beam (steel/concrete) doing section from section definition in RSA.

Now I don't need any reinforcement, but I would like only to know the Plastic Moment of the section, to compare with the only steel section. Could I use Steel section design tool to do that? what i need, It is something like steel section Moment + Concrete section Moment partialized with the neutral factor n.

For example, if you have a steel beam with on top a concrete slab, you can find Plastic moment of the whole section after calculated the neutral axes.

Thanks

Re: Composite Beam

Romanich — Thu, 30 Mar 2023 10:49:57 GMT

Hi @Michele100100 ,

You can get plastic moment from the Section Definiton:

Re: Composite Beam

Michele100100 — Thu, 30 Mar 2023 11:09:06 GMT

thanks, but is that of the concrete section, steel or both together?

Re: Composite Beam

Michele100100 — Thu, 30 Mar 2023 11:31:55 GMT

The Plastic Moment that Im looking for is the Resistance Moment of the composite section: for example if was only a steel S275 section IPE180, Mrd = Fyd/1.05 x Wpl,y = 275MPa/1.05 x 166414.93mm3 = 43.58 KN*m.

In composite section, the Wpl,y you shown is both sections together? some like weighted values?

Many Thanks again.

Re: Composite Beam

Romanich — Thu, 30 Mar 2023 11:42:02 GMT

Marked with * - weighted values

https://help.autodesk.com/view/RSAPRO/2023/ENU/?guid=GUID-3C08787E-34CE-4FB0-B0B0-DFDC50EA9E8E

Re: Composite Beam

Michele100100 — Thu, 30 Mar 2023 12:25:47 GMT

thanks

Re: Composite Beam

Michele100100 — Thu, 30 Mar 2023 12:37:41 GMT

Sorry, one more things:

What does it means Base Material in the first window? Because if I choose steel I have at the end a Wpl,y* value, if I choose concrete, I have a different Wpl,y* value.