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Simple formwork for triangular concrete pour?

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structures2020

Structural
Jun 7, 2020
3
BM
Hi there,

I need to pour a triangular wedge-like shape with mass concrete about 4' high and 4' wide. What is the simplest way of getting this shape with standard formwork materials (ply and 2x4s)? Interested in potential form options without closing in the top face of the triangular shape.

Ideally would've liked to pour mass concrete and let is create its own slope.

 
 https://files.engineering.com/getfile.aspx?folder=2dd6ab14-a9d3-4886-9d7a-8f9783a5caf6&file=triangular_wedge.png
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Without forming the (45 degree) sloped surface, use very low slump concrete (less than 3"). Have workers (concrete finishers) begin immediately . Don't require tight tolerance on dimensions or surface finish; will be a "best efforts" project.

[idea]
 
Is this unreinforced concrete?

Either way, you don't want to pour concrete to a sharp acute point at the top or bottom as you have shown. It will eventually break off. I would form that sloped face and leave about a 3-4" minimum shelf on the top as access for you to birdmouth the concrete in. You will need to run a vibrator down that birdmouth opening to get proper consolidation otherwise that formed face is going to look awful with voids and bugholes.

That is going to be hard to pour that without forming that front face. I'm not saying impossible but hard.
 
Can it be poured like a triangular column, then moved to its final position after curing? To reduce its weight, you could create a void with a sonotube or triangular form which would remain in place after curing.

BA
 
Structures2020,

Turn your shape upside down, build the form, use release agent liberally and vibrate religiously and strike off and tool the surface. Then remove the form and use the shape.

You have said nothing about loads, reinforcement requirements or connections required so I have not addressed any of things, but they will all need review, along with many other things. As has been noted by others, these sharp edges may need to be rounded over to get this shape to release.

More information will result in better outcomes.

Jim H
 
What is the purpose of this triangular prism? Is it connected to a foundation or is it a foundation?

BA
 
Use reglets (small blocking?) at the angle location to prevent a sharp concrete edge.

Dik
 
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