WHY IS THE CONCRETE PATCH NOT IN THE HOLE?
There are only two directions the patching materials can go to get out of a drill hole. And that's up, or down thru the hole. Whether your drilling for termites, slab raising, mudjacking, or it's just a hole that's no longer being used needs to be in a slab, so you need to seal the hole.
Too many do it yourselfers and contractors simply fail to properly prepare the holes which would help secure the patching materials in the concrete. There are some simple things you may what to try which may keep the patching materials where you need it to be.
First, after materials you may have injected, you will need a masonry drill bit at least 1/16 of an inch larger than the original drilled holes. You are only going to drill an inch into each of your drill holes. This will tapper the drill holes narrowing them downward which will prevent any type of patching material, which stays intact, from easily moving downward thru the holes.
Next, you'll need to clean the dirt, cement dust, and any other materials from the sides of the drilled holes. You can use a water hose, compressed air, a pipe cleaner brush, or even a tooth brush if you're just dealing with a few holes. This will help the patching material bond to the concrete side walls of the drill holes better.
Now, you're ready to install your Poly Plugs by Pest Boys, or a similar product, into the drill holes to support whatever patch material you're going to be using. Different patching materials may recommend thinner depths or thicknesses needed for their product to cure properly. So read the labels and set your plugs to the recommended depths. The plugs only need to last until whatever patching material you use, has the recommended time to cure. If you use paper materials to support a wet concrete mixture patch, the moisture will be absorbed by the paper before your mixture cures, and both may fall down through the holes completely.
Poly Plugs by Pest Boys are a closed cell material which will prevent water from passing them down into the holes. So if rain is coming before you can patch or inject a material down underneath, you can install Poly Plugs by Pest Boys, leaving them partially out above the slab. Then the rain won't drain down through underneath the slab. After the rains pass, you can then remove them, inject your materials, reinstall them, and patch the holes.
Now that the holes are ready to be patched, you'll need to mix your concrete. You must only add the recommended amount of water to your concrete patch. Too much water will weaken the concrete patch which will allow it break up easier into smaller pieces after curing. The smaller pieces will then fall down through the holes.
These simple steps may only help prevent your patching materials home falling down through the drill holes. There are several thing's which may provide enough pressure from beneath the concrete slabs and force the patches up thru the top.
Hopefully I have provided you with some information on how to help keep your patches from falling down through the holes, and stay where the patches belong.