Justification for cutting through rebar
Justification for cutting through rebar
(OP)
I have to write up a calculation which justifies cutting through rebar in a underground concrete wall which is a part of a pullbox which houses underground cables. Basically we're making a 4" diameter core drill and cannot avoid cutting through horizontal and vertical rebar. The rebar is 1" diamter and has a 7" vertical spacing and 6" horizontal spacing. The wall is 14.5 feet tall, 10 feet wide and is 12 inches thick. Any tips on how to calculate this would be helpful.
Thanks in advance.
Thanks in advance.






RE: Justification for cutting through rebar
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Justification for cutting through rebar
RE: Justification for cutting through rebar
Otherwise, you may be looking at replacing the structural contribution of the cut steel, somehow.
As a side note, if uyou must cut the steel and the wall spans vertically, cut the horizontal steel. If it spans horizontally, cut the vertical steel. The impast structurally will be far less.
Hopefully the wall does not span both directions, but effectively can.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Justification for cutting through rebar
RE: Justification for cutting through rebar
In fact, if this associated with a nuclear plant, strength to resist soil pressure may not be the conrolling issue here. It may be explosive in nature.
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Justification for cutting through rebar
I would venture to say that reinforced concrete design is one of the more complicated aspects of structural engineering. It would be best to involve a structural engineer here.
Good luck!
RE: Justification for cutting through rebar
RE: Justification for cutting through rebar
RE: Justification for cutting through rebar
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Justification for cutting through rebar
If they absolutely must hit the bar(s), then you would need to calculate the wall forces (per code) and determine the capacity minus the bars that were cut (per ACI 318).
It is beyond this forum to get much further into it, best bet is to get with a Structural Engineer for these calculations.
RE: Justification for cutting through rebar
RE: Justification for cutting through rebar
RE: Justification for cutting through rebar
leist22 calls this a pullbox, I think this is what I would call a drawpit, basically a manhole for cable installation.
I tend to agree with ukengineer58 that this might not be critical. I guess the wall has rebar on the inside and outside face, perhaps only the rebar on one face will be cut.
RE: Justification for cutting through rebar