Pressure grouting

[wrantler]

I am looking to use cementitious grout under pressure to fill a void under a footing. Drill relief holes in the top, form and pressure grout from the bottom.
does anyone have any tips on how to spec the grout procedure. I supposed there would be a gradation to the grout mix and a max/min pressure for the pumping.

Any thoughts in general of past experiences I would appreciate.

 

[emmgjld]

Search for Compaction Grouting. I have used Hayward Baker for a couple of challenging projects.
If you can= find a relatively local Specialty Contractor and discuss the issues, you may learn a lot, real quick. I have found that while trying to spec the grout sounds real good, a lot of local differences in the sand aggregate can spell success or failure.

 

[MotorCity]

For what its worth, every time I've seen pressure grouting performed, its been done through the top of a surface (not the bottom side). Depending on the load, type of application, and size of voids, you may want to look at several grout types (cement based, expansive, etc)

 

[gte447f]

Is this for residential or commercial application. If residential, this sort of thing is usually done in my area by specialty contractors without any specifications from an engineer. There are cementitious grout options and urethane foam options. For residential footings, I usually recommend underpinning with discreet piles instead of grouting. I usually recommend grouting for slabs on grade.

 

[OldDawgNewTricks]

Before getting into the specifics of the grouting procedure, the first order of business is to determine what caused the void under the footing. Has the cause been abated, or might the problem reoccur?

 

[milkshakelake]

I'd post in the geotechnical forum. I posted there recently about pressure grouting and got good advice.