Development length of nonstandard hooks

[cwipf]

I need to develop a #5 epoxy coated rebar from a bridge parapet into an 8" slab. The bottom clearance is 1". Therefore, the hook is only embedded 7" into the slab. Can I achieve full development by extending the tail of the #5 bar?

 

[Lion06]

I, and many other engineers I know, use this clause all the time. It's especially helpful for a PT where you need to develop a top bar within the thickness of a wall that can be 8" less cover.

A stirrup is a bar in tension so I see no difference from a mechanics perspective.

 

[cwipf]

Lion06, I'm still not sure 12.13 would apply here. If it does, then why did ACI publish 12.10 & 12.12 dealing with development length? I would assume the continuous slab and longitudinal rebar within the bend would provide some resistance to splitting, but I do not know how to quantify that. Right now, we are assuming a partially developed hat bar. We assume the partial development is linearly proportional to the (actual Ldh)/(required Ldh) ratio.

rapt, I am not familiar with your code references. Do you have a minimum required radius to consider the additional extension for #5 bar?

slickdeals, I don't think I can design it as a corbel since the height of the parapet is large compared to the base of the parapet.

 

[Lion06]

This article addresses the very use of this provision that we're discussing.

http://www.structuremag.org/article.aspx?articleID=1210