Common RC Column Configurations

[medeek]

I'm trying to put together a matrix of the most common RC Column configurations. Here is what I have so far:

With the circular columns is it more common to weld the transverse ties into circular hoops or to just hook the tie around adjacent longitudinal bars. I don't have a lot of real world experience with RC so I'm learning.


A confused student is a good student.
Nathaniel P. Wilkerson, PE

http://www.medeek.com

 

[dik]

I posted a cad drawing a bit back showing layouts... have to run, but if you do a search, you should be able to find it. I'll upload it again later.

Dik

 

[MotorCity]

No reason I can think of to weld the ties, just hook them around an adjacent bar. Be mindful of the angle of the hook, there is a specific seismic hook detail in ACI

 

[dik]

FYI...

 

[KootK]

ACI's detailing manual may be a document of use to you (clip below). CRSI has similar information (attached). I'm often surprised at how not uniform column detailing actually is. Some firms priorities certain things at the expense of others: seismic performance, access holes for pouring, minimum rebar quantities... I've also seem some pretty exotic, if not always practical, tie details that sacrifice symmetry with the intent of allowing more bars to go without ties (6" business).

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.

 

[slickdeals]

For circular columns, the new ACI codes require you to lap 6" and turn them into the column core with hooks.
For your third square column, you would either need 2 crossties or none at all (assuming you don't have more shear in one direction than the other). If clear spacing between bars exceed 6", you need them to be "tied"
Same for the rectangular columns.

 

[rapt]

The use of single leg fitment with 135 and 90 degree end hooks is subject to limitations.

Must be alternate ends where there are multiple of them in one direction and their use is limited based on concrete strength and axial load in ACI318-2014.

Otherwise, 135 degree hooks are required at both ends.