I remember reading in Family handyman years ago about having to hire a company that would inject some material under the slab to raise up a corner that settled.

Is that the only way to lift up a corner of a square of a concrete walkway that has settled somethking like 1/4 - 1/2"?

 

It's called mud jacking. They pump mud under the slab to raise it. My father had it done back in the early 60's to fix the sidewalk on the side of the house.

 

thanks! Is that the only way to fix it? Is that a DIY thing?

 

I doubt it's a diy job, it takes a big pump and then it helps to have the know how so you don't create another problem. About the only diy way I'd know would be to pry the slab up and force dirt under - praying that you don't break the concrete while doing so. Maybe some of the others will have more ideas.

 

There are other options...you could grind down the high area so it's less of a trip hazard. You could have the one section of walkway cut off, lifted up a little, and add some gravel or even concrete underneath to realign it. You could have the one section cut off, removed, and have a new section poured.

AFAIK, mud jacking is not a DIY as it requires the ability to pump concrete slurry at high pressure. The other options could certainly be DIY depending on your skill set.

IIWM, I'd probably ignore it unless it got a lot worse. But if I had to fix it, I'd probably cut the end section off at the first joint line, raise the section with a spud bar and fulcrum, and pour a little mortar with fine aggregate under that corner.

The problem is, once you separate a section of the walkway, it's easier for it to move and the problem might actually get worse over time.

 

thanks guys. I was wondering if someone was going to say to stick a large / long / strong rod under that corner, llift it back up.... and then what : ) Fill with gravel / etc but likely can't really get under it with just that small amount of lift. I don;t want to cut it for sure. I'll leave it be for now. thanks!

 

Mud jacking (injecting grout/cement) is an option. Because of the equipment involved and trained operator it's best if you have a bigger job as it's likely to be a couple hundred just for them to show up.

Yes, you can raise the slap Egyptian style. You may need to saw completely through the slab at the control joint to separate the piece you want to raise. Then lift up that section any way possible. An excavator will do it very easily but you can also use a lever and fulcrum. Once it's up you can spread sand or crushed stone underneath and re-set the concrete.

 

Actually today they use a urethane foam rather than concrete. I had a walkway that had a couple of low spots that settled and they leveled it up about 4 years ago. So far everything is ok.