Help forming 2-inch-thick concrete walls

[Cooler]

This company manufactures 2" thick concrete panels.  Their specifications might be a good road map.

https://slenderwall.com/

[mad_planter]

I need to build/create a 24” pedestal to support some yard art. Currently looking at a square column with a 12” square base, 2” thick walls narrowing to an 8” top. I have mixed my share of concrete for slabs, post holes etc. But no experience filling 24’ of a 2” void. Suspect keeping the mud loose and a lot of tamping and knocking. Any suggestions?

Bill

why not just make it as slabs and use pins, holes, and concrete specific epoxy to join it together?  although being tapered I guess that would be a challenge. Another possibility would be to build a interior box out of blue board, and then just do one side at at time, putting temporary sides on the side you are working on and pouring it in and troweling it flat.

I think that a 12" square with 2 foot high walls is going to be heavier than expected.

[Cooler]

We have a customer who makes hardware for wire mesh reinforcing fabric for cast concrete drain pipes (like you see on the side of highways).  The wire mesh has to be centered between the inner form and the outer form.  We make the spacers that keep the mesh centered.

Our smallest spacer places the mesh in the middle of a 2" thick form.  As far as I know all concrete pipes have this mesh between the sides of the forms before pouring.

Our largest spacers allow two layers of mesh for a 3 or 4 inch thick wall.

I think you need that type of mesh or the thin concrete will crack.  You will have to make some sort of spacer to keep the wire mesh from poking out of the concrete and touching the forms. 

They sell the mesh at the home centers.  They typically show considerable amount of rust but since it is all hidden, that is not an issue.  You can also use fence mesh if it is easier to come by.

[brianwelch]

why not just make it as slabs and use pins, holes, and concrete specific epoxy to join it together?  although being tapered I guess that would be a challenge. Another possibility would be to build a interior box out of blue board, and then just do one side at at time, putting temporary sides on the side you are working on and pouring it in and troweling it flat.  

I think that a 12" square with 2 foot high walls is going to be heavier than expected.

A different take (and look) might be to use bluestone pieces and fasten together with epoxy and inside corner reinforcing

[mad_planter]

We have a customer who makes hardware for wire mesh reinforcing fabric for cast concrete drain pipes (like you see on the side of highways).  The wire mesh has to be centered between the inner form and the outer form.  We make the spacers that keep the mesh centered.

Our smallest spacer places the mesh in the middle of a 2" thick form.  As far as I know all concrete pipes have this mesh between the sides of the forms before pouring.

Our largest spacers allow two layers of mesh for a 3 or 4 inch thick wall.

I think you need that type of mesh or the thin concrete will crack.  You will have to make some sort of spacer to keep the wire mesh from poking out of the concrete and touching the forms. 

They sell the mesh at the home centers.  They typically show considerable amount of rust but since it is all hidden, that is not an issue.  You can also use fence mesh if it is easier to come by.

precast pavers are less than 2" thick with no obvious reinforcement.  He'd probably be all right for something that isn't load bearing.

[Cooler]

precast pavers are less than 2" thick with no obvious reinforcement.  He'd probably be all right for something that isn't load bearing.

Probably.  But I've seen videos of concrete counters being poured and they have always included reinforcing mesh. Those are not load bearing and they are probably around 2" thick.

[mad_planter]

Probably.  But I've seen videos of concrete counters being poured and they have always included reinforcing mesh. Those are not load bearing and they are probably around 2" thick.

good point.

[GEB]

Put a partial void in the middle.  Build your outside form, then your inside form is  a square box, or a piece of 4" PVC as a form.   You have thicker walls at the bottom, but it is still lighter weight.

Too much of a hassle so forget the thin wall idea and fill the mold and go easy with the vibrations. Thanks all for your contributions. 

Bill

[toolmiser]

How about using something like a "sonatube" (carboard tube) in the center. It would still be hollow but stronger and easier to pour.

[Cooler]

How about using something like a "sonatube" (carboard tube) in the center.  It would still be hollow but stronger and easier to pour.

I poured a sonotube 12" x 30" column to support a deck post.   I drove in four rebars to the ground and attached some light gage fence wire to the four rebars. 

I was not working on any instructions, so that might have been unnecessary, but like chicken soup, "it can't hurt".

I simply assumed that the concrete needed reinforcement.  I did not read that anywhere.