What gravel/crushed stone should you use when mixing concrete?
For 20Kg of cement, we used 36-40L of gjutegrus and 32-36L of 8-16 macadam. (after a few rounds you get the right eye measurement)
Throw in all the macadam and half of the sand into the mixer, run it for a few seconds, add the cement, run it for a few seconds and throw in the rest of the gravel, spray water at the innermost part and let it work its way out, but be careful, it becomes too loose quickly, so be sparing with the water.
Throw in all the macadam and half of the sand into the mixer, run it for a few seconds, add the cement, run it for a few seconds and throw in the rest of the gravel, spray water at the innermost part and let it work its way out, but be careful, it becomes too loose quickly, so be sparing with the water.
What strength are you thinking of, you take 1 part cement to 3 of sand as they say, and 2 parts 8-16 macadam, then it becomes strong and good for a footing for the wall.
The footing should be about 15 cm wider on both sides if it's clay-like ground, otherwise 10 cm is enough with a thickness of about 15 cm if there is a lot that will stand on the wall.
The reinforcements should be placed about 5 cm from the bottom for the best support.
Don't forget to measure everything to ensure it's equal, and the less water you have, the stronger the concrete will become, but it can be difficult to handle if it becomes too stiff, to get it to spread out. The concrete should be vibrated in some way so that water comes to the surface.
The footing should be about 15 cm wider on both sides if it's clay-like ground, otherwise 10 cm is enough with a thickness of about 15 cm if there is a lot that will stand on the wall.
The reinforcements should be placed about 5 cm from the bottom for the best support.
Don't forget to measure everything to ensure it's equal, and the less water you have, the stronger the concrete will become, but it can be difficult to handle if it becomes too stiff, to get it to spread out. The concrete should be vibrated in some way so that water comes to the surface.
Use the same ratio 20/36/32 and about 11 liters of water.X xLnT said:
And mix thoroughly, at least 10 mins in the tombola per batch
Now I went in and checked the contents list of different grovbetong.
Weber: Aggregate: natural sand 0-10 millimeters. Max grain size: 12 millimeters
Byggmax: A dry mortar consisting of cement, sand (grain size 0-6 millimeters), and admixtures.
Combimix: Grain size ≤ 12 mm
Not much coarse aggregate here.
Weber: Aggregate: natural sand 0-10 millimeters. Max grain size: 12 millimeters
Byggmax: A dry mortar consisting of cement, sand (grain size 0-6 millimeters), and admixtures.
Combimix: Grain size ≤ 12 mm
Not much coarse aggregate here.
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The ballast is more like filler and reinforcement of the concrete, stone does not sink or compressAndreas Lundgren said:
It's difficult with all the proportions, especially since sometimes it refers to kg and sometimes liters. What does "1 on 3" mean, 1 volume part cement and 3 volume parts sand? (And then 2 volume parts gravel 8-16 mm.)R rävlyan said:
Regarding the measurements and reinforcement planning, I have to stick to the construction drawing so that the person responsible for inspection is satisfied.
I also have the slab for the neighbor's garage on one side.I usually use a couple of buckets, about 10 liters each: 1 of cement and 3 of sand, and 2 of crushed stone, plus a smaller bucket that matches the water amount that seems right. This way, you have all quantities in the correct ratio all the time. To vibrate, you can use a hammer drill (not a dinky toys one), perhaps a Hilti or similar; they strike well. Don't dump all the concrete at once; half is good, and vibrate so it flows out and water comes up.
Sure. If it’s any consolation, I have a couple of gate posts that turned out incredibly hard with my mix. I had trouble drilling for the gate. I use the right proportion of cement in my recipe and as little water as possible. W/C ratio of about .50 is where it usually ends up.This is for a footing that will support the entire garage and the earth masses underneath, so I'm trying to find out as much as I can. For piers and the like, I totally get that you use whatever you have!
Yes, I know it will turn out well, but I simply can't sleep when you have like the same amount of sand and macadam, and someone else has 3:2, byggmax has 2:1, etc. There must be a recipe that is best, arghhh!X xLnT said:I gave you the simplest possible, gravel and stone in Liter (read buckets) and a 20Kg sack of cement. Just go for it now
Gravel is for filling so you don't need as much concrete and it becomes just as strong, but as mentioned, mix well, the cement should be everywhere in the mix, too little sand and aggregate makes the concrete brittle.
No, not actually from what I can see...X xLnT said:
For the slab, it says "400 mm Tjälldéngrund with insulation and concrete" (whatever that means) and then further about reinforcement, insulation, drainage, etc.
Then it states:
- Safety class Foundation: SK2
- Safety class Floor on ground: SK1
- Climate class: Concrete in exposure class XC1
But I'm going to take my chances, soon it will be too cold to pour anyway! I'll mix extra cement and mix with a bit of water, we'll see. Otherwise, I'll just have to break it up in the spring when it's time to pour the slab.