MAXIMUM SPACING IN COLUMN BARS

[Dan.M.M]

I have a column of size 600mm by 300mm and was wondering if there should be a provision for maximum spacing. Since BS 8110 and Eurocode 2 do not state this provision.

 

[cliff234]

I am pretty sure that ACI 318 likewise does not specify a maximum spacing between column vertical bars. Accordingly, years ago, I arbitrarily decided that 18" is the maximum distance that I'll permit between column vertical bars. This means that a 24"x24" column is the largest column for which I would use a 4-bar pattern. Other maximum permitted bar spacings are specified elsewhere in ACI 318 (such as maximum spacing between bars in slabs, walls, beam stirrups, etc.) and the upper limit between bars never exceeds 18". Therefore the 18" dimension between column bars seems reasonable to me. That said, for your column, measuring about 12"x24" (I think best in inches and feet), I would use a 6-bar pattern.