The photos aren’t the best but I could use a little help here
The concrete stoop in the back at the top of the steps and in the front had huge gaps with nothing under them. The landscaping was flowing away from the slabs so i have no idea what caused this. The front stoop was settling and cracking because of it and the back was just starting to crack. The gaps were huge. If the entry holes were big enough I could have fit my head in there. When I looked under I could see the the bottom of the gravel that they had poured the concrete on.
What are some possible causes of this and how is it remedied?
If those are steps, it’s not structural. Could be due to voids or air pockets in the mix at the form edge. Sloppy job, but aesthetic only unless it’s structure. If steps, just patch it for cosmetic reasons.
I don’t know what a cut and fill lot is. Its obviously not structural but i think it’s going to keep cracking so patching it seems useless. Doesn’t it? It was like Carlsbad caverns under there.
Landscaping and hardscaping can settle for this same reason as well as just due to poor compaction if the grade was raised at the location of the hardscaping.
Your situation is settling below the entire patio and that void below needs filled to prevent further movement. If there is a slope adjacent to the hardscape and there is eveidence of erosion then the addition of retaining systems may be necessary.
Thanks Cameron. It was not cut and fill. So slabjacking and some monitoring to see if the soil compacts anymore? Or would it be best to just start all over?
Personally I would get a load of CA-6 sand/gravel packing mix and start shovelling it in and packing it back as far as possible into the voids. Slabjacking would be the most they need to do and not where I would start. But keep in mind you could(and probably should!) just refer it to a landscape contractor and let them decide what is best.
still great info. Thanks for the replies.