Wide Beam Connections
Wide Beam Connections
(OP)
What type of things I need to consider to frame a 4' wide beam into a 2'square column? Also where would I look to find information on this type of connection?
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RE: Wide Beam Connections
I would look at the shear at the face of the column using b=24" instead of b=48"
RE: Wide Beam Connections
RE: Wide Beam Connections
Mike McCann
MMC Engineering
RE: Wide Beam Connections
RE: Wide Beam Connections
RE: Wide Beam Connections
Had I not known anything about your job and I saw a 4' wide beam framing into a 2' wide column, that would definitely stand out to me.
RE: Wide Beam Connections
Office buildings also use a similar system using 'shallow wide' beams that are typically 6 ft wide and 18" deep.
A narrower beam than column is a detail to stay away from based purely on framing costs.
RE: Wide Beam Connections
RE: Wide Beam Connections
RE: Wide Beam Connections
OK... PT construction, banded tendon layouts with wide beam strips and small columns.
I thought the standard way to handle the wide PT beam strip and small column scenario was to provide drop caps at the column, boxed or tapered, whatever, when needed for shear in order to limit and/or optimize the design depth of the PT slab.
Am I missing something here?
Mike McCann
MMC Engineering
RE: Wide Beam Connections
My answer applies to wide beam to column connections. Banded tendon layouts like you use in the US for flat slabs is not something I agree with, but not relevant to this thread.
RE: Wide Beam Connections
Please bear with me here...
I don't understand why not. Aweb11 is talking PT here, and banded or not, the same shear distribution problems can exist. Banded tendon strips are, essentially, wide beams in the PT slab.
The drop panel just increases the allowable punching shear from the column, allowing more load in a smaller area to get be sucked into the column. This shear capacity can even be increased further with special studded metal strap embeds criss-crossing the column centerline.
Mike McCann
MMC Engineering
RE: Wide Beam Connections
I am not sure we disagree on much here, but the OP was asking about a 4' wide beam going over a 2' square column. Hardly a small column. I didn't agree with some advice he was given, so said so. SEIT's advice was wrong, and I thought yours and civilperson's advices were off point. After my comment, and perhaps before he read it, tngolfer also gave poor advice. For the record, Galambos and apsix understand what I wrote and agree.
RE: Wide Beam Connections
Cheers.
Mike McCann
MMC Engineering
RE: Wide Beam Connections
RE: Wide Beam Connections
DaveAtkins
RE: Wide Beam Connections
I had pictured a beam of roughly the same depth as the width or even deeper than its width. In this case, I am sticking with my bigger column recommendation unless you can show the column can handle the moment. I still think if you need a beam that big your column may not be able to handle the fixed end moments from your beam.
RE: Wide Beam Connections
That is too simple. The moments distribute in proportion to the stiffness, so a bigger column will attract more moment. The column doesnt have to "fix" the beam, it just has to take its share of the moment. Take the case of a big concrete beam supported on a relatively tiny steel column. Pinned connection, but the beam can still work.