can't achieve hook development length

[Structures33]

Hey there - What do we do when we can't achieve hook development length? For example, a concrete column w/ #6 verticals sitting on a 14" deep footing. The #6 hook development length for my condition is 17". I can't get 17" into the footing and the footing can't be any deeper.
Thanks in advance

 

[frv]

Look at ACI 12.5.3

This gives you some options.

If all else fails, you cold provide higher strength concrete to reduce ldh.

BTW, I don't know where you're getting 17". Higher than any number I have.

 

[csd72]

Can you get sufficient steel by using smaller bars? Do the bars need to develop full strength or is part strenght acceptable.

You can also use a proprietary stress block at the end of the bar to take the stress.

http://www.erico.com/products.asp?folderid=173

Also be aware that compressive forces dont develop along a hooked bar.

 

[COEngineeer]

Did you multiply it by .7 or other factor according to 12.5.3?

Never, but never question engineer's judgement

 

[Structures33]

Thanks for the responses.
Multiplying by .7 is something I will do to feel better... although I'm not certain that we will have the adequate cover required because this is being constructed in the Middle East and there is no quality control.
And yes 17" is correct for our conditions. Concrete strength is low.
I'm going to check the capacity again - I may have some wiggle room there b/c the moment designed for at the top is lower that that at the bottom and it's the same r/f.

 

[jike]

I assume that you are trying to develop in tension and not compression. Is this correct?

Use more dowel bars to reduce the embedment by the ratio As provided to As required.