Deflection of a perforated Beam

[Leo Baldwin]

Trying to find moment of inertia in^4) for a steel beam that looks like the attached (22 gauge steel).
Finding MOI for any beam is easy if it has no side holes.
Not sure if it helps, but I can actually have SolidoWorks FEA analysis done to get the total deflection.
I need to find the MOI (in^4) to be able to quickly get deflection calc with varying loads/spans.

 

[rb1957]

instead of just shearing the holes in the web, you could take a page from our industry and use flanged lightening holes ... easy to stamp out and almost improve the structure and save weight.

another day in paradise, or is paradise one day closer ?

 

[MIStructE_IRE]

I don’t doubt that they’re sexier.

I also don’t know what impact they’ll have on vierendeel bending, but I’m sure its not good.

 

[Leo Baldwin]

The smaller (and larger) holes are there to provide maximum fusion of EPS that goes around these z-profiles.
It's the EPS that provides lateral support to the z-profiles. This whole thing is already being manufactured since the 80ies... No fancy FEA back then... I think they made a whole bunch of different strips and tested them... Picked the one with least amount of failure and deflection...

 

[dik]

I suspect the aircraft industry takes advantage of the weight loss caused by those 'little holes'.

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

-Dik

 

[MIStructE_IRE]

OK, sorry, I thought someone had just butchered a Z purlin and wanted to justify it! I got the wrong end of the stick completely!

 

[dik]

FYI...

https://www.newsteelconstruction.co...m_campaign=new-steel-construction-sept-2021_7

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

-Dik