Mud Jacking Specification 1

[eric1037]

I have a project where a homeowner had some cracking and settlement in his basement floor slab.

After coring through the slab we found voids ranging from 1/16" to 1/2". The slab is underlain by a pea stone below-slab drainage system.

We would like to grout the voids and raise the slab slightly in a couple of areas where it settled.

My fear is that if the grout is too thin it will infiltrate the voids in the pea stone and render his below-slab drainage system useless or at least reduce its capabilities.

Has anyone had experience with this type of problem? If so, how do we test the grout to ensure it is thick enough? Is there a maximum slump or a flow cone value that would be appropriate?

Thanks is advance!

 

[Burr]

The original use of pea stone is the problem. Round stone settles because it does not have a locking surface. Knowing the original GC screwed up doesn't help now. My reco.....since the pea stone has probably found equilibrium, lay thinset (with fiberglass mixed in) on top of the areas that have settled.