Mud Jacking a pinned slab - Contractor Talk - Professional Construction and Remodeling Forum

davitk · 11-09-2008, 08:48 AM

A repeat customer called me last week to evaluate a concrete slab that had settled approximately 4" (I didn't pour it). The wife had walked out the door and onto the step and it went "KABOOM" and dropped

she isn't fat

Apparently it was pinned to the concrete wall with 1/2" rebar, the wall was covered by 1" styrofoam, covered by vinyl and the slab poured up to that; when I looked at it you could see a gash in the foam, and with a flashlight saw the rebar. A mud jacking company had been there before me and claimed they could lift it with no problems but of course had not seen and/or not pointed out the rebar to the HO. At my suggestion the HO called the mud jackers to pose the 'rebar binding and not allowing the slab to raise evenly if at all' question, and they reassured that it should be no problem and had encountered this before.

Any opinions??

KennMacMoragh · 12-02-2008, 11:03 AM

So there was only rebar around the edges anchoring it to the stem wall? No rebar in the middle of the slab? Hard to tell without a picture, did it crack and just sink 4" in the middle?

davitk · 12-02-2008, 02:04 PM

Turns out the rebar didn't bend but broke; ran a sawsall blade and removed the ends. Apparently the slab raised just fine as I haven't heard otherwise

KennMacMoragh · 12-02-2008, 10:29 PM

Curious to see how they did it.

woodmagman · 12-02-2008, 10:40 PM

Quote:

Originally Posted by davitk

A repeat customer called me last week to evaluate a concrete slab that had settled approximately 4" (I didn't pour it). The wife had walked out the door and onto the step and it went "KABOOM" and dropped

she isn't fat

Apparently it was pinned to the concrete wall with 1/2" rebar, the wall was covered by 1" styrofoam, covered by vinyl and the slab poured up to that; when I looked at it you could see a gash in the foam, and with a flashlight saw the rebar. A mud jacking company had been there before me and claimed they could lift it with no problems but of course had not seen and/or not pointed out the rebar to the HO. At my suggestion the HO called the mud jackers to pose the 'rebar binding and not allowing the slab to raise evenly if at all' question, and they reassured that it should be no problem and had encountered this before.

Any opinions??

Not seeing a picture of this and based on what you are saying, I would cut the slab loose from the house, likely the ½ inch rebar; one inch from the wall can not handle the shear or weight. And the rebar may never have been anchored properly. I would think that that slab should have been poured directly to the foundation wall with the dowels epoxied in place.