Will this work for a stand

[OscarA]

Hi everyone.
I'm still in the planning stage and want to run something by those with more knowledge about structural strengths of stands etc.
I have a heap of 110W 390L 190H concrete blocks.
I would like to know if they are suitable to use without having to double them up. Here is a very rough drawing of the shape of the stand. I will double them up at the ends as you can see and they will be 4 blocks high with a brick curtain at the top.
Hope this makes sense.

[dmun]

For those who don't speak French: the blocks are 4.3" wide, 15.3" long and 7.5" high.

They will work fine, I don't even think you need the front-to-back wall, one cross wall should be support enough.

The reason we don't use what we call 4x8x16 blocks more in the US is that you can't do the dry-stack-and-fill method, as the cavities are too small. Mortaring block walls is a bit of a challenge for masonry novices. This tool makes the job a little bit easier.

[Karangi Dude]

Hey OscarA,
I think the 110mm bloks would be ok but you would need to use rebar and core fill them, but that would be a bit hard to do as they are so narrow. I suppose if you used a thin core fill say using quarter minus (a size of small crushed blue stone) instead of the the normal size used in standard concrete that wolud be much easier to poor. Using double blocks at the ends won't add much extra strength because you are not tying them in to the corses they are just sitting along side of the other blocks, but they will act as a pier in someway I suppose. A suspended slab is self supporting so long as you use 12mm rebar @ 300 centres you dont need to use bricks suported by agle iron as this will weaken your joints especialy on those narrow bricks.
I hope this will help explane what I mean, by the way I like your idea of putting crossed rows in the middle that will certainly help distribute the weight.
Cheers Doug.

[OscarA]

Thanks for the reply guys I really appreciate it.
So it looks like I can use them but I'm just a little confused about using bricks for the curtain/boarder as it will weaken the joints as you say Doug. Are you saying this because the bricks must sit on the blocks therefore reducing the amount of slab that'll be resting there. If so the bricks I plan on using are 50mm wide and I was going to have them sitting 30mm on the blocks and 20mm overhanging. That'll leave 80mm for the slab to make contact with the blocks and rest on.
Is this enough or should I drop the brick idea and think of another way of decorating the slab. That's all it really was just a way of making it look nice.
I can always tile around the slab with terracotta or similar.
Thanks again guys I love this site.

[Karangi Dude]

Hey OscarA,
I would have the suspended slab go right to the edge of the blocks, for the max amount of strength and worry about the curtain and decoration later. BTW where will the opening be which side of the stand?
Cheers doug

[OscarA]

Hi Doug

The opening will be at the bottom of the pic which has the two spaces side by side. I am going to put shelves in there and a couple of doors. The side openings will be were I store the wood. Might also put doors there to keep the weather out.
Can't wait to start this build but as we have christmas at our house this year I'm not aloud to start until christmas is over