How do you fill the holes?
After the concrete is raised with mudjacking material, a foam plug is inserted into the hole, and the hole is patched over with cement. The concrete is ready for use immediately. It is however, recommended to allow the patch material to set-up before use, typically a couple of hours.
The foam plugs help RaiseRite patch the holes, and it acts as a shock absorber, when slabs are affected by the frost cycle. Holes that are not patched with foam can pop out, when the material and earth under the slab expand from freezing.
When concrete is raised with polyurethane foam (FoamJacking), these plugs are not used. The material used for raising the slab replaces the inserted foam plug as a shock absorber.