Development length of stainless steel rebar

[penpal97]

There is guidance for development lengths of black bars and epoxy coated bars, but what about galvanized and solid stainless steel?

Anyone have any thoughts? Is the stainless surface just as slick as the epoxy? or even more smooth?

 

[larsacious]

In ACI 318-08, 12.2.4(b) it states that "For uncoated and zinc-coated (galvanized) reinforcement, psi,e = 1.0." Thus meaning treat it just like non-epoxy coated.

As far as stainless, I would assume you treat it the same as non-coated except you must use a higher value of fy in the development length formula. Please note that section 3.5.3.1(c) lists the ASTM which stainless must be deformed to. Also 3.5.3.10 gives guidance on what value to use for fy for stanless since the stress-strain curve is not as well defined as mild steel.