Badly cracked garage concrete floor

[debian0001]

Hey guys,

I just got a quote from a company between 4K to 5K to rip and replace the concrete in my garage. It's badly cracked. Has anyone done it themselves before and was it really hard? I don't really want to shell that much cash. I feel if I try it myself and ruin it, I can always have them do it then...

By the vacuum cleaner is the worst spot. It's like spider web cracking. I was thinking at least that area, I could try to cut out a square and put in new concerete. For all the lines, I think I can angle grind them, then fill it. Even if I get 2 - 3 years out of it, I think it would be better than spending 5,000. This garage is really old but solid... I also don't think it would add that much value to the house so I'd rather do it myself.

 

[herm0016]

8 to 10 per sq foot for remove and replace if you are getting a decent deal on a 4 inch slab with not too much work on the base.

LOL at "is it a lot of work"

either someone as practicing their hulk smash in there, or there is a serious problem with the base material. i would remove, take out a 6-12 inches of base, fill back in with recycled concrete road base compacted in 4 in lifts and pour with fiberglass reinforced cement. that would probably cost more than 10 per sqft though.

 

[feralkid]

Holy subsidence batman!

How long has it been like this?

 

[Greenman]

Hey guys,

I just got a quote from a company between 4K to 5K to rip and replace the concrete in my garage. It's badly cracked. Has anyone done it themselves before and was it really hard? I don't really want to shell that much cash. I feel if I try it myself and ruin it, I can always have them do it then...

By the vacuum cleaner is the worst spot. It's like spider web cracking. I was thinking at least that area, I could try to cut out a square and put in new concerete. For all the lines, I think I can angle grind them, then fill it. Even if I get 2 - 3 years out of it, I think it would be better than spending 5,000. This garage is really old but solid... I also don't think it would add that much value to the house so I'd rather do it myself.
View attachment 19421

It's pretty easy to do. Dig out your 60 pound electric jackhammer, break it up, toss it in your dump trailer or a dumpster. Make sure you have a solid 6" of rock base under it, throw in a grid of number 4 rebar 16" on center. Then set your screeds, set up the pump and 3 or 4 friends to help you screed and finish. Be sure someone knows how to finish concrete and has the tools or you'll regret it every time you walk in there.

Btw. There is no repair for that slab. It's failed catastrophically. Anything you do is throwing away money. Replace it or ignore it.

 

[Micrornd]

throw in a grid of number 4 rebar 16" on center

Here we would use 6" fibre-reinforced concrete without rebar (on a compacted base, of course)
We use that for semi's and such parking and access roads for county and state facilities.
Do you not use fibre-reinforced ready-mix in Cali ?
Or is it too expensive there ?
Saves us time and money here !

 

[Greenman]

Here we would use 6" fibre-reinforced concrete without rebar (on a compacted base, of course)
We use that for semi's and such parking and access roads for county and state facilities.
Do you not use fibre-reinforced ready-mix in Cali ?
Or is it too expensive there ?
Saves us time and money here !

Fibre reinforced concrete isn't used much around here, not because of cost but performance. It doesn't prevent differential movement once the concrete cracks. There is a lot of expansive soil around here (clay) so steel is the goto reinforcement.

 

[Micrornd]

Yeah, I forgot things move more out there than here, well except for sinkholes.
Our fibre stuff doesn't crack unless overloaded, even with age (I placed some of the first here almost 40 years ago), as
We have orange and blue clay here in cntrl. FL but it is very scattered, much more is in the north and panhandle of the state, for the most part we are "dirt" and sand here.
It makes an excellent stable compacted base, pretty easy to achieve 96-99% compaction.

 

[Greenman]

Yeah, I forgot things move more out there than here, well except for sinkholes.
Our fibre stuff doesn't crack unless overloaded, even with age (I placed some of the first here almost 40 years ago), as
We have orange and blue clay here in cntrl. FL but it is very scattered, much more is in the north and panhandle of the state, for the most part we are "dirt" and sand here.
It makes an excellent stable compacted base, pretty easy to achieve 96-99% compaction.

Clay packs very well, till it gets wet.

 

[PowerEngineer]

Yikes! I'm thinking this looks like the result of poor preparation of the ground under the garage slab. If so, then perhaps removal followed by better preparation and a repour is the way to go (and I'd use rebar while I was at it too). Makes me wonder if you have checked the foundations of your house...

 

[jmagg]

You can probably save a G or more if you remove and dispose of the old yourself. A 16 lb sledge will do the job if no rebar and it looks like not. Youll need at least a pickup and hopefully someone that takes clean fill.

 

[Greenman]

Yikes! I'm thinking this looks like the result of poor preparation of the ground under the garage slab. If so, then perhaps removal followed by better preparation and a repour is the way to go (and I'd use rebar while I was at it too). Makes me wonder if you have checked the foundations of your house...

Clearly no steel in it, and probably 3 sack mix over ground that was never compacted.
I've seen old slabs that were 2" thick, I've seen them loaded with whatever chunks of metal were laying around, including forks, knives, and spoons.