Slurry is the heavy, water-based mixture of soil or clay, sand, and cement that traditional mudjacking pumps beneath a sunken slab to raise it.
In depth
Mudjacking slurry typically weighs more than 100 pounds per cubic foot, compared to a few pounds for polyurethane foam. All of that weight sits on the same weak soil that allowed the slab to sink in the first place, which is a major reason mudjacked slabs often re-settle within a few years.
Slurry is also water-based and erodible. The same washout that created the original voids can slowly wash the slurry away too. And because slurry needs large injection holes, often 1 to 2 inches, the repair is more visible than modern methods.
How Acme applies it. We do not pump slurry. We lift concrete with lightweight, water-resistant polyurethane foam through much smaller injection ports. The material will not wash out, adds almost no load to the soil, and cures in minutes instead of days.
Related terms: Mudjacking, Polyurethane Concrete Raising, Soil Washout, Injection Port
Frequently asked questions
Why does slurry fail when foam does not?
Weight and water. Slurry adds thousands of pounds onto already weak soil and can erode. Polyurethane is a fraction of the weight and hydrophobic.
Is mudjacking with slurry cheaper?
Sometimes on day one. But re-settlement and repeat repairs frequently erase the savings over the life of the slab.