Round stirrup in 4-bar configuration in a round column??
Round stirrup in 4-bar configuration in a round column??
(OP)
My fabricator would rather do a circular tie than a square tie. Is it permissible to do this in a circular column if I only have four vertical bars?.......or is there some place in the code that I'm not seeing that specifies that one must use a square stirrup for only 4 vertical bars?
Thanks
Thanks






RE: Round stirrup in 4-bar configuration in a round column??
That being said, however, I never use less than 6 in a circular column. Just personal preference here. I also don't allow the lateral spacing between the bars to exceed 6".
Mike McCann
MMC Engineering
RE: Round stirrup in 4-bar configuration in a round column??
"Where longitudinal bars are located around the perimeter of a circle, a complete circular tie shall be permitted."
The argument could be made that the circular tie with 4 bars violates the 135° limitation of 7.10.5.3, since the circular tie would be tangent to the bar. However, I am not sure I would make that argument.
RE: Round stirrup in 4-bar configuration in a round column??
If you want circular ties, do not allow lap splices of the ties, but normal bent ends - 180 and 90 - and have the contractor alternate where these coneections to the vertical bars occurs along the length of the column.
Mike McCann
MMC Engineering
RE: Round stirrup in 4-bar configuration in a round column??
I agree with you. The philosophical question is whether the ties are in a square pattern or four-on-a-circle. That is the point I was trying to make (rather poorly).
RE: Round stirrup in 4-bar configuration in a round column??
msquared48, is there a problem with just butting the ends of the tie together and welding the stirrup?
I'm using these concrete piers in an application where I'm trying to raise TS columns above the animals that occupy the same space. Due to customer preferences, I have a pier that is WAY bigger than it really needs to be.....hence my question a week or two ago regarding minimum reinforcing steel below 1% of the gross area.
My biggest issue on these piers really is uplift..........and making sure that the forces in my steel column get transfered down to the spread footing below. Due to the MWFRS design that I'm using, there's hardly even any shear at the base of the TS column / top of conc pier so I'm really not stressing things out in compression that much.
What do you think about the welding?
Thanks.
RE: Round stirrup in 4-bar configuration in a round column??
Curious why you say that you can't have 135 degree hook on circular ties. Done all the time, just not on the same bar like at a corner in a rectangular column.
RE: Round stirrup in 4-bar configuration in a round column??
If you use 4 bars, you would have to check the capacity at different rotations of the bar pattern (single bar at top or 2 bars at top) to determine the lowest capacity.