Pipe Columns - Rigid Connections

[bpstruct]

Have a project requiring pipe columns as primary supports (4) for a freestanding canopy. Can't brace the frames - any guidelines/suggestions on creating rigid connections with these pipe columns? I don't think the owner is going to be happy about knee braces either.

 

[msquared48]

Cope and weld the H#)) out of the pipe column beams where they intersect the pipe columns and call it good.

A sketch and better description of the proposed members for the structure would be in order here.

Mike McCann
MMC Engineering

 

[hokie66]

Cap plate, maybe stiffened by knife plate through column, depending on the moments involved.

If the beam part is also circular, you might consider having the beam and column rolled as one piece. Lots of highway signage is done that way. You can make a bolted splice in the beam if the whole thing is too large to transport.

 

[DWHA]

Gussets plates and knee braces sure help with rigid connections.

 

[ToadJones]

you may consider moment connections in the form you see on cantilevered stop light poles.

 

[bpstruct]

This is what I was thinking...not sure about the "knife plate" although I think I've convinced myself that it needs to be horizontal to connect to the bottom flange. See attached.

 

[azcats]

Any chance you can cantilever the columns and not need the fixity at the top? The increase in pipe might wash out the cost of all the field welding.

Lots of other things to consider with a cantilever though...

 

[Teguci]

Cap the pipe, stiffeners to the beams, cap the beams.

 

[msquared48]

You can weld up a two way "Knife Plate" to be inserted into precut vertical slots in the top of the pipes and weld it off. Then bolt the "W" shape beams to the knife plates, cope and weld the top and bottom flanges to the pipe column. As mentioned, weldinng a cover to the top of the columns is a good idea too.

Mike McCann
MMC Engineering

 

[S275]

For stiffened base plate carrying moment, see this link it might help you

http://www.microstran.com.au/lmc_gallery_base.htm

Good luck

 

[asixth]

Cantilever the posts from the foundations and provide rigid connections for the frames where beams frame over.

 

[JedClampett]

I think you're going to be surprised on the amount of deflection you get and not in a good way. Even the small amount of lateral wind on the exposed sufaces of the roof members is going to result in 2 to 3 inches of deflection or more.