Thin cladding panel

[ztengguy]

Any thoughts on a 2" thin cladding panel? Panel will be about 7'-0" x 4'-0" spanning horizontal. My worries are rebar shadowing, and also spalling. Granted they will be vertical, but the bars will only have 3/4" cover.

per ACI I can do 3/4" cover on a precast wall.

Im iffy about going so thin.

 

[CBEngi]

You could consider Fiber Reinforced Concrete or Welded Wire mesh Reinforcement.
I'm assuming since its so thin its not structural so your just trying to meet minimum steel.

 

[ztengguy]

Well, it will have lifting and handling stresses, which might control.

 

[dhengr]

Ztengguy:
Ask a couple local precasters if they can do them, and what they would do in the way of reinforcing, lifting, etc. Generally, I’d think they should be handled, lifted and transported on edge, so you don’t have them being stressed in the weak direction during handling. You could make a 6'-9" x 3'-9" flat/plane rectangle, with tight corner bends out of a #4 bar to reinforce the edges. Then weld a sheet of welded wire fabric to this edge reinf’g. cage. You might also thicken 3 or 4" all around the panel. This might actually be needed to facilitate securement and lifting hardware.

 

[ztengguy]

This is actually for a precaster. he is looking for reasons not to pour it 2", he knows its not the best idea. I think it will come down to here is what can happen, do you still want to use a 2" panel.

 

[asixth]

Don't really know how close the reo needs to be to the surface before shadowing becomes an issue. I have seen it happen for insitu wall and column construction when it comes to about 5/8". I don't think 3/4" cover would be a problem for a precast panel. The placment and vibration is pretty good.

I wouldn't want to use a 2" panel. Even if the walls were timber or metal framed I would want them to be a minimum 3". I remember calling up a 6" panel one time and the local precast supplier wanted a minimum 7.5" because it works best with his waterproofing detail.

I don't know if you guys use AAC facade panels in the US but even those panels are normally a minimum 2.5" thick.