Perimeter Beams in Flat Slab System 1

[struggle67]

Hi Good Day Everyone,

May I know what is the slab panel load should be carried by the perimeter beams in a suspended flat slab system? I couldn't find any guideline in Eurocodes. If you guys are familiar with Eurocodes, I would really appreciate your help! If I recall correctly, in BS code those beams are required to carry 1/4 of the slab panel load and in ACI I think those beams stiffness are required to calculate and distribute accordingly within the column strip.

Here in Singapore local practices,
Those beams are designed to support only walls (cladding) at the perimeter of building and tie columns. Then flat slab is designed separately to carry floor loadings without carrying wall load although I believe those perimeter beams will be attracting the slab panel load not only wall load as it is stiffer than the slab and homogeneous with the slab.

Thanks

 

[rapt]

Struggle,

Normally a triangle of slab will be supported by the beams as well.

But it all depends on the relative stiffness of the beam and the parallel slab.

If they deflect the same amount under their respective loads that you mentioned, then the beam will not support any of the slab load. If the beam deflects less, then it will support some of the slab load.

Often in Singapore, designers ignore T beam action as well and only use the beam web as the beam. I would always consider the T-beam and it will carry at least the load on the T Beam flange. Plus possibly extra depending on relative stiffness as above.

 

[struggle67]

Hi RAPT,

Thanks for helping me out again!

I believe the same and fully agree with you. But I am just looking for an eurocodes reference/clause to support my statement when I talk to qualified professional engineers here. Without any document support, they won't listen to a young engineer like me as they've been doing this for their whole life.

Thanks

 

[rapt]

Design codes normally do not define things like that. They will tell you to design for the load the beam attracts.

They assume an engineer knows how to estimate the design load based on his engineering knowledge and understanding.

A good example of this is the argument over Mxy moments in FEM analysis/design. I asked the AS3600 committee for clarification as people said the code did not cover it. The response was that the code does cover it. The code requires that equilibrium be satisfied, and that requires that the designer accounts for everything that affects equilibrium. So Mxy must be included in design!

 

[struggle67]

Thanks RAPT

Maybe I am very hopeful(a bit frustrated) to find something directly related to this in Eurocodes as I found one in BS. If there is no direct clause then I will have very slim chance to convince them.
but when in Rome....