Additional Rebar

[torogiak]

hello guys,

the foundations and first floor columns (installed with 10 pieces of 16mm diameter rebar)for a four story building were already concreted. We decided to revise the fourth floor where it accommodates additional load. The contractor revised the structural plan, eventually it needs a total of 12 pieces 16mm diameter for a column. Are there remedies to add additional 2 pcs of 16mm dia. to the second floor? What's the best recommendation.

 

[msquared48]

What do you mean that the contractor revised the column steel? Who is the structural engineer of record? They should be doing that, not the contractor.

Mike McCann, PE, SE (WA)

 

[zakmuh]

Hi,

You would need to provide additional bars around the existing column (with links) and reconcrete it to strengthen it. Instead of 2, 16 dia bars, provide 3 12dia bar on each face (12 in total). This is an overkill but no other options!

You would also need to check existing footing capacity whether its adequate enough to accommodate increased load. If you need to increase its dimention, add extra size with dowwel bars.

Hope this helps.

Cheers

 

[hokie66]

Ask the structural engineer to sharpen his pencil. Or else, try to take advantage of any overage in the actual concrete strength. Adding 2 small bars to a column which has already been cast is silly, if I understand what you are asking. If you mean adding bars to columns which have not yet been built, what is the problem?