Edge beams with balustrades check

[MoStructEng]

Hi
A graduate here. I am using Tekla to design a steel frame to Eurocodes and I've got edge beams with balustrades I did a bit of research and the max allowed deflection for balustrades is 25mm which is about 1.3 degrees only. When I try to limit my torsion and torsional rotation the section that work are astronomical in size, also note that I've got intermediate beams coming in as shown in pic attached that are simply supported to the beam so I assume these provide some sort of restraint. I think that when Tekla does the analysis these incoming beams are not considered to provide restraint. Is there another way for me to check the Balustrades effect on the beam ? Should I model the beam as simply supported with a span equal to the distance between the incoming beams rather than the entire beam length? How do you design beams with balustrades? Any help would be appreciated

 

[KootK]

For the sake of the deflection / rotation check, moment fix the infill beams to your edge beam as that will likely be a better reflection of reality. Then, do a qualitative check to ensure that the real world detail for that connection likely will provide some rotational restraint to the edge beam. Standard clip angles and shear tabs will usually do a pretty good job in this respect.

 

[MoStructEng]

More info:
I've used 0.814kNm/m as a torsional UDL along the entire beam. The balustrade has got a connection every two metres should I instead apply a single torsional load at where the balustrade connects to the beam? (I haven't done this because I don't really know the exact location of these points). the pic above is just for refernce but its the one below that is causing me issues, distance from support to support is 6.22m and incoming beam is at the middle. The rotation comes out to be about 3.5 degrees, section is a 356x127x33

 

[MoStructEng]

Thanks KooTK, I did try fixing the incoming beams. Not sure about the detail as this is an early stage design

 

[KootK]

You steer the detail if you need to. Or, at the least, you try. Another common approach is to use small angle kickers / fly braces run from the bottom flange of your girder back to your infill framing. You might run similar kickers up to your floor slab at tighter intervals if you have a floor slab that would be somewhat robust.

 

[dik]

I'd just treat the torsion from the ballustrades (unless something exceptional) as a torsional load per foot (m) and multiply that with the spacing of the intermediate beams to determine the moment at the intermediate beam. If anything significant, I'd check the design for the added moment; this is not likely an issue if the intermediate beams are simply supported. I'd then make sure the ballustrade was secured to the edge beam. I'd then grab a glass of scotch and call it a night.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik