HSS beams in an industrial building - need to cap ends?

[Rainbowtrout]

I have HSS beams in an industrial building - solid waste place. I was wondering for the HSS beams hanging in the air, is it necessary to specify a cap plate to seal the moisture out. We typically do it for all HSS columns but this is my first time with beams.

What do you typically do? What has your experience been like?

 

[Stenbrook]

I put cap plates on all my discontinuous HSS members, beams or columns, etc. My opinion is that it is relatively cheap to put on and better safe than sorry.

 

[Rainbowtrout]

I forgot to mention that all members will be painted.

 

[MikeHalloran]

What you need to seal out is all the solid waste dust/crap that can accumulate and cause/catalyze poultice corrosion. Paint can't do that.



Mike Halloran
Pembroke Pines, FL, USA

 

[BUGGAR]

Keeps the birds out too.

 

[XR250]

As Buggar says, Birds and also wasps

 

[KootK]

Does one still provide a bleed hole to drain internal condensate? Or does the need to shut out external corrosion agents override that?

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[kingnero]

Having demo'd structures with capped and open HSS's,
this is my take: when capping, corrosion only takes place as long as there is "free" moisture and oxygen inside. After an initial amount of rust, the oxidation stops due to lack of one (or more) of the components that is needed for the oxidation process.
Open HSS's that are not galvanized (nor having any other type of coating), tend to rust, in an environment that does not stop to supply the components. After time, they are substantially worse than the capped HSS's.

Bleed holes for galvanization process are another subject, but I guess that's all common knowledge.

 

[BUGGAR]

Good point, Kingnero: In my marine work I try to add a fabrication note to locate galvanizing holes/vents to drain water after installation. I do a lot of galvanized railing along the waterfront.

 

[Rainbowtrout]

Thanks for the inputs! I will cap all ends no matter where they are![pre][/pre]