Posted: 3/28/2012 3:50:52 AM EDT
|
Yesterday I helped a friend pour a small rat wall where he is expanding part of his outside wall to make a larger kitchen area.
How long should the concrete cure? (It is 42 inches deep.) Thanks for any info. |
|
Quoted:
Is it cold where you are? The slower the cure the harder the concrete. Is there any forms to strip? Good question. It will be 64 degrees today and cool down to about 50 degrees for the next three days. No freezing temps are forecasted for lows at night for the next 10 days. |
|
Quoted:
What's your next step? Frame on top? Today is fine Backfill? How tall is wall? Temp? PSI poured? Are you going to compact backfill? I usually wait at least a week before any earth work Yes, frame on top. Wall will be standard 8 feet (oh, maybe 7.5 feet in the expanded kitchen). We used 25 bags of concrete/cement mix he bought from Home Depot and did the pouring ourselves. (This wasn't a real long new rat wall, maybe 10 feet.) We used wood "molds" all the way down for the 42 inches and will remove once it has cured. But I ain't sure about how long that would be? Than backfill soil will come in contact with the cement after the mold is removed. ETA: He is a general contractor and said "two days is all we need". I said, "wait a minute, that don't seem long enough". He knows alot about this stuff but two days doesn't seem long enough. But he is a general contractor. |
|
Quoted:
How was it secured to the existing foundation? Did you vibrate the mix in the form as you poured? What was the psi rating of the mix? Posted Via AR15.Com Mobile We put in metal rods to secure to the existing foundation and at intervals/spacing my friend said I should drill, etc. Yes we vibrated the heck of the mix as we poured and that part I am pretty confident went properly. I don't know what psi mix he bought but he is a general contractor, so I assume he bought the right stuff. I just can't remember what the psi was. |
| Completely depends on the mix, but everyone is right that the longer it sits, the stronger it will be. I allow traffic on CG-9 (concrete entrances) after 48-72 hours, but that's a high end mix (A-3) compared to what most likely ended up in that pour. If he has the time, you're probably good to wait as others suggested. |
|
Quoted:
Completely depends on the mix, but everyone is right that the longer it sits, the stronger it will be. I allow traffic on CG-9 (concrete entrances) after 48-72 hours, but that's a high end mix (A-3) compared to what most likely ended up in that pour. If he has the time, you're probably good to wait as others suggested. Although I don't remember the mix he used I am SURE it wasn't an A-3 mix. Well, I'm not positive but I would be VERY surprised if it was that strong. |
|
Is your buddy going to put some sort of treatment on the concrete? I know I was watching an episode of that one show (with that dude and that chick that were rebuilding a house.... HOMETIME! That's it with JoAnne Liebler (she's hot) and they were working a foundation for a new home they built and used tar and foam insulation on the exterior before they backfilled...))
Might be something he would want to consider... but then again, he's the general contractor. 
|
| Concrete will hit 75% of its 28 day strenght in 7 days. So if you odrered for example a 3000 psi for a wall and didnt have it too wet you should be able to start setting on it with-in 2-3 days. The stiffer you poured it the stronger you will see that 28 day number. |
|
Quoted:
Concrete will hit 75% of its 28 day strenght in 7 days. So if you odrered for example a 3000 psi for a wall and didnt have it too wet you should be able to start setting on it with-in 2-3 days. The stiffer you poured it the stronger you will see that 28 day number. I use to do concrete work and we always waited atleast 28 days to back fill but all ways strip forms the next day. One interesting thing I learn was a local company uses man made sand instead of natural sand in their mix. The down side to this is the man made sand weighs more and since concrete is batch by weight you get shorted on you order. If you order a yard you would get around 3/4 of a yard the up side is the psi rating goes up quite a bit. In our case were pouring 5000 psi mix and the first cylinder break test was around 8000 psi. |