4 inches thick with a thickened edge about 1 foot square. Compacted sub base. Steel mesh reinforcing with rebar around perimeter. Very dry sumer
2006-10-02 01:11:39 · 8 answers · asked by Anonymous in Home & Garden ➔ Do It Yourself (DIY)
You don't say, but I assume your slab dimensiond are in feet. If it was this big, you can expect to get some cracking from expansion and contraction. Normally, you'd put in an expansion joint for a slab this size, or at least cut in a surface joint to control where the slab cracks.
So, to answer your question, it is not unusual you have a crack in the concrete. It would be expected and in fact, you probably have several hairline cracks in your slab. If your slab is exposed to the weather, you might want to consider applying a sealer to the surface.
2006-10-02 03:24:30 · answer #1 · answered by Jeffrey S 6 · 0⤊ 0⤋
No it's not normal. I understand your concern, one question did you after you poured the concrete and waited about 4-5 hours keep the surface wet? (I believe your concrete just dryed to fast) you see keeping the surface wet would not have any effect on the cureing of the concrete but what it would have done was to help it cure in a more natural time frame, what you could have done to help the concrete was to lay a water hose on your slab and turn the water on gently, put a board under the end where the water is comeing out so as to keep from washing the surface to hard, (make sure the whole surface gets wet) and keep it wet for at least a day. Years ago we used to lay burlap on the surface and then wet it, I don't know if they do this any more. But those who know will wet it. I understand you didn't want a crack to come in your slab, lets hope it's the only one and only a hairline crack. There is not much that you can do about the crack, that would be lasting. I would like to help, but maybe next you might ask someone befor tackling an unknown, I am 76 and still learning, it's like measuring twice and cutting the board once. Good Luck
2006-10-02 01:56:18 · answer #2 · answered by obac777 2 · 0⤊ 0⤋
Cracks in slabs is a very common problem. Many times this is because the concrete had too much water in it when it was poured. People tend to add water to make the concrete easier to place but this practiced leads to excessive contraction as the concrete cures.
Concrete cures very quickly at first and then the process slows down but continues for many months.
2006-10-02 01:47:58 · answer #3 · answered by oil field trash 7 · 0⤊ 0⤋
Yes it is normal. In fact, I'm surprised it took 6 months. My shed is on a 14x20 slab, 6 inches thick. It cracked within a 2 months. The mesh and rebar will hold everything in place. No worries...
2006-10-02 01:26:01 · answer #4 · answered by Anonymous · 0⤊ 0⤋
The type of soil will dictate how deep the beams and how much reinforcing you need. That being said if you have expansive soil, the moisture level will build up after placement and cause movement... All concrete cracks, some crack in many small cracks you don't see, others crack in fewer but larger crack you do see.... but yes you should have stabilized the soil with moisture before placement.
2006-10-02 01:45:14 · answer #5 · answered by Ibredd 7 · 0⤊ 0⤋
It is absolutely normal, all cement type material will crack some.
From your description you did a great job of preparing the sub base and used the proper reinforcing for this type of slab.
2006-10-02 05:08:45 · answer #6 · answered by familysport 2 · 0⤊ 0⤋
Yes- its normal for concrete slabs to crack, thats why they put expansion joints in them, they move and expand with the Seasons.
2006-10-02 01:16:07 · answer #7 · answered by Anonymous · 1⤊ 0⤋
No, it's not "normal" but certainly not unheard of. Did you cut an expansion joint? Did you keep it wet so it wouldn't dry out too quickly?
2006-10-02 01:21:43 · answer #8 · answered by Burford Bigelow 4 · 0⤊ 0⤋