Shorten Concrete Slab

[Canucks1010]

Hi All,

My Client has an existing concrete slab that he wants to cut back by approximately 2 feet. The slab is 12" thick and 48" wide, with a single layer for rebar at the top and bottom.
Cutting back the slab poses no structural concerns. I am just wondering how we should finish the cut end - ie. when cut, we will have a surface with exposed rebar.
What would be the best path forward to protect this cut end? I was thinking one of the following

1. Bush hammer back to expose 2" of existing reinforcement. Then case a grout end cap to achieve 2" of concrete cover.
2. Similar to the above, but cast new concrete.

Would exposing the existing rebar be required, or can we just bush hammer to roughen the surface and cast a 2" cold joint with grout?
Is there an epoxy coating I can use instead to avoid casting concrete/grout?


Many thanks!

 

[r13]

Assume the cutback is the length, not the 4' width, I would cut 3' strip or longer, clean the exposed rebars and roughen the hardened surface, then re-concrete. If the cutoff is along the width, I probably will do nothing.

 

[SlideRuleEra]

Unless the slab is in a corrosive environment or appearance of the cut area is critical, apply zinc-rich paint (cold galvanizing) to the exposed rebar.

http://www.SlideRuleEra.net

 

[MIStructE_IRE]

Fosroc do some good products where 5mm of the stuff is equivalent to 35mm of ‘real’ cover. Contact them to discuss.