Max Spacing of vertical bars in walls

[CRQUT]

Hi all,

Curious to get opinions on the attached for max spacing of vertical bars, specifically clause AS3600 cl.11.7.3. and the 350mm requirement.

If the bars are staggered as per attached then max spacing between vertical 'parallel' bars is around 240 if they are spaced @ 400 on each face and offset diagonally. Would you consider this in accordance with the code or is the intent of the code for the bars each face to have a max spacing of 350mm?

Contractor is using a permanent formwork product which dictates bars at 200mm increments.

Thanks for your thoughts.

Regards
CRQUT

 

[rapt]

I would have thought it applied to bars in each reinforcement grid, so bars on each face.

 

[rscassar]

Permanent formwork doesn't really dictate increments of 200mm, there is still plenty of space in a permanent formwork system to nominate 300 or 350 centres. It just mean the sub-contractor needs to use their tap measure instead of placing 1-bar in every cell or every second cell.

 

[CRQUT]

Thanks Rapt for reply, if that is the intent then any chance the long awaited, highly anticipated commentary could clarify?

RSCASSAR - I agree but the templates for the starter bars would no doubt clash with the internal ribs of a permanent formwork system at some point. Which means more crane time taking it off again, cutting it and then placing again. If they cut ribs then the chance of the base blowing out is increased. I try to minimise the impact contractors can have site when it comes to cutting things. My other concern is the vertical dropped in the wrong cell with out the starter.

Its a detail that has been proposed and I was asked to have a look at it and comment.

 

[GTD_18]

I would agree that it's per grid or per face.
The code is generally written noting "per face" arrangements.

 

[blihpandgeorge]

i would've expected per face. as for permanent formwork wall systems, they need LOTS of care on site, they are notorious for not having proper compaction / placement and being full of voids. The NSW building commissioner is very vocal against them.

 

[rapt]

Long awaited Commentary is at the printers.

It will not help to clarify this one.