Help me pick between two designs

[Gulf]

In another thread you mentioned "DenSheild." A Georgia Pacific product which is made from gypsum. I recently retired from GP ( different division). However, I don't have any experience with that product.

[terdferguson]

Thanks Gulf. I looked through your album. Absolutely amazing!

[david s]

If it's a boundary fence you may be in contravention of local regulations. In Australia most councils require anything to be 1.5 m inside a boundary fence.

[terdferguson]

In the forno bravo instructions for the casa2g it calls for using angle iron for support across the front of the stand. But since I'm making an arch, I don't want to do that right? I planned on doing something like what RandyJ did in post #83 in the link below. Does the width of my opening matter when doing it this way?

[UtahBeehiver]

Full arches are self supporting. Angle iron is a lintel for the block or brick flat span.

[RandyJ]

How wide are you planning to make your front arch? I think mine was only like 24" wide but I am sure you could go a lot wider. Make sure to leave enough on the sides for support. Mine is also tied into the block side walls. Although I am sure I don't even need anything there as my slab is like 6" thick, but the front arch is 11.5 " of rebar and concrete. It won't go anywhere.

Randy

[terdferguson]

As depicted above in design #3, my arch would be 40" wide to allow for me to line the inside of it with bricks. I was going to do something like you can see below. Is there a standard ratio of width to height of the arch for structural soundness? Or is the arch height just a matter of personal aesthetics?

[Gulf]

As long as there is the proper rebar in that arch, you could park a tractor on top of it. My arch was done that exact same way. It only spans 32", but it could have spanned another 8" with no problem. I poured mine monolithic with the hearth slab and feel that I could have took the arch up another 4" in the middle, but I am pleased with what I have. It is hard to tell from the pic, but the ends are sitting on 8" of block just as is depicted in your drawing.

[RandyJ]

As gulf said I can not see a reason that would be a problem. Lots of rebar and let it set up real good before you pull the forms. And I would also have it core fill the bricks at the front there too for additional strength. But that should be just fine. Now you just have to figure out how to form it up.

Randy

[UtahBeehiver]

Gulf and I did similar mono pours, mine spans about 44" with rebar tied into the main hearth floor grid.

[terdferguson]

Thanks guys. Beehiver, that's interesting. It looks like the ends of your arch don't sit on the blocks but just abut them. Is that correct?

[UtahBeehiver]

No, they are intergrated into the adjacent cores of the CMUs.

[Gulf]

And that is just fine. As Randy said "fill the core at the front". The weight is still transfered to the foundation through the reinforced concrete inside the cores. The plans say fill every other core. But all corners and ends of all openingings need to be filled. Even if that means doubling up. I was just noting that my design and yours were the same. Both designs work fine.

[david s]

As long as there is the proper rebar in that arch, you could park a tractor on top of it. My arch was done that exact same way. It only spans 32", but it could have spanned another 8" with no problem. I poured mine monolithic with the hearth slab and feel that I could have took the arch up another 4" in the middle, but I am pleased with what I have. It is hard to tell from the pic, but the ends are sitting on 8" of block just as is depicted in your drawing.

American tractors must be pretty small. That thing would only be big enough to fit an Australian ride on mower.