Hooked Vertical Bars in Foundation Wall - Hook not long enough

[CBSE]

Same project I'm working on doing the PM. I came in after all of the rebar has been installed and the hooked length of the vertical #5 bars for the foundation walls are 6 inches. Code requires 12db which is 7.5 inches.

Foundation is as follows:

16" deep x 24" wide footing
36" tall x 6" wide stemwall - #5's vertical and horizontal at 12" o.c.

light framed construction on top

Are there any alternatives solutions other than removing the vertical bars and redoing them?

 

[KootK]

Write someone a nastly letter bitching a quality control and then just let it go in exchange for a little contractor good will to be spent later down the line. I don't see the vertical bars being of much importance in this application. Maybe T&S and a general connectivity between wall and footing. It's unlikely that the bars are serving as shear reinforcing.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[CBSE]

I personally have the same view, however, I'm not the EOR, and the EOR does not have this same view.

 

[KootK]

I see. It's tough to suggest a fix without understanding what job it is that the EOR sees the vertical bars doing. Some ideas:

1) Maybe there's enough bar length available to bend the hooks into code compliant 180's?

2) Perhaps the concrete strength could be increased such that straight bar embedment would work?

3) If it's not a shear friction thing, you could add more bars and use a prorated straight embedment capacity on each.

I think that all of these options would make the contractor feel sufficiently spanked if that is the goal.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[CBSE]

What do you mean by straight embedment...I'm curious. That was my original thought, the footing is 16" deep, what embedment would be required?

This is the same engineer that is requiring 4,500 psi for a standard foundation to support a stick built 2 story structure that is only about 2,200 sqft.

 

[KootK]

By straight embedment, I just meant the vertical embedment that would be required if there was no hook at all.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[dcarr82775]

Maybe Add straight vertical bars with the A req'd / A provided adjustment on development length. Add enough bars to be equivalent to #5 @ 12". At that point probably easiest to just take them out and put in the right ones as silly as it seems

 

[manstrom]

How much tension are those bars really seeing? Seems silly to require a full on hook.

When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.

-R. Buckminster Fuller

 

[CBSE]

I got no where with the engineer on this one. The hook to me is pretty much useless in this application. The only place I would say that it would be necessary is at the hold-downs where there is direct tension into the wall. Other than that, for the most part, should be purely shear transfer.

It really is silly. We are taking out the bars now and replacing them...pretty costly miss on this one. I came in to the PM position after all the rebar was laid. Somehow they laid bars without a shop drawing submittal that was required.

 

[KootK]

How does a non-standard hook even come to be? Field bent? I'd have to think that a rebar supplier would know better.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[CBSE]

KootK:

I'm not sure. I spoke with the rebar supplier and concrete supplier and both were surprised when I pointed out the standard hooked detail and the required "db". My story is that they looked at the " 6" Minimum" length and just started bending. I'm guessing they have been doing this for a while and it finally got caught.

 

[KootK]

Well that's comforting.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[CBSE]

For that reason I have now reworked my own rebar schedules to show required lengths instead of leaving it up to the contractor to do math :/

 

[BUGGAR]

If you suspect a supplier has been furnishing bars that could fail (in other more critical applications than yours), what is your responsibility to notify code authorities?