mud jacking and slurry

What is Cement Slurry and How is It Used in Concrete Repair?

You’re reading up on concrete repair and/or mud jacking and you have run across the term “slurry” and want to know more about this industry term. Don’t ya just love industry terms that contractors throw around like you’re supposed to know what they mean?

Anchor Foundation Repair Bryan College Station

At Anchor Foundation Repair, we use slurry in three of our four main service areas and can tell you *more than you ever wanted to know* about slurry. We use slurry for concrete repair, but also during our slab foundation repairs and as part of the tunneling process.

This article will focus in on the use of slurry in our mud jacking process to repair sunken and uneven concrete surfaces. We will define the term, explain how and what it’s used for, and review its benefits over other options available to homeowners for raising concrete.

What Is Slurry? What is Slurry Used For?

Slurry is a mixture of topsoil, Portland cement, and water. Specific to our area, we use a Brazos River topsoil that is sifted and fine-filtered before mixing with the cement and water. 

The topsoil choice should be tailored to your area if you’re not here in the Brazos Valley.

slurry for concrete repair

If slurry sounds a little bit like mud, that’s because it IS quite a bit like mud. The consistency of the slurry is different depending on its purpose in the repair project. The slurry is made thinner and more watery for filling purposes and thicker and with less water for lifting purposes.

We’ve already mentioned that slurry is used in foundation repair, under-slab tunneling, and concrete repair. So in foundation repair and under-slab tunneling, the slurry is used as a filling material and is of a thinner consistency like pancake batter. 

In concrete repair like we are focussing on today, it is used as a lifting agent and is more of a cookie dough consistency. Are you getting hungry or is it just me?

How Slurry is Used in Mud Jacking/Concrete Repair

concrete raising and leveling in Bryan College Station

Slurry for concrete repair is used for lifting sunken concrete slabs back to their original elevation and slope. This method has a name and it’s called mud jacking. Hooray for more fun industry terms . . . 

Mud jacking is a form of concrete repair that lifts a concrete surface from below by injecting slurry underneath the slab of concrete using holes drilled through it. 

The slurry is pumped in using a pumping machine at a higher pressure setting for lifting concrete (as opposed to a little lower pressure setting used for filling). 

The slurry “jacks up” the concrete to the desired position, similar to a car jack lifting a car for changing a flat tire. Cement slurry both fills in the area under the slab and is also strong enough to lift because it is a thicker material.

In other words, slurry is used in mud jacking to lift and hold the concrete back where it’s supposed to be. Mud-jacking concrete that is still in good shape (just crooked) is a great alternative to fully removing and repouring new concrete.

need mud jacking BCS

Benefits of Slurry Used in Concrete Repair

Using slurry for mud jacking in concrete repair has many benefits. One is that it is a time and money saver over the full replacement of a sidewalk, driveway, or patio. Mud jacking uses simple materials that don’t cost much. Mud jacking also costs less than the labor and materials for a tear-out and full replacement.

after mud jacking Brazos Valley
Same driveway as image above, done in 1 day

Mud jacking takes a few hours or a couple of days versus taking all the concrete out and making it again, which could take a week or more. 

Just like slurry’s other uses, using it in concrete repair minimizes the opportunity for future settlement of the concrete surface and prevents erosion and washout under the concrete slab.

One other benefit of using slurry and mud jacking is that it’s a more natural material and not a chemical substance. Some people might like that over a similar method that uses the same concept but a different lifting agent. Not to mention that this more natural material is also cheaper than the chemical materials used for lifting concrete.

To put all these benefits in a nice neat list, here ya go. The benefits of using slurry and mud jacking for concrete repair are as follows:

  • Cheaper process than full replacement of concrete
  • Faster process compared to full replacement of concrete
  • Minimizes opportunities for washout and erosion under concrete
  • More natural material than other concrete raising methods
  • Cheaper material compared to other methods of concrete raising

Are There Alternatives to Slurry and Mud Jacking?

There is an alternative to mud jacking and it’s called polyjacking. Instead of the slurry used in mud jacking, polyjacking uses a high-density polyurethane foam product. Polyjacking is used in both foundation repair and concrete repair (but not with under-slab tunnel filling).

mud jacking and concrete raising and repair

Slurry and mud jacking are great, but polyjacking has some great qualities too, and can be a better fit for homeowners in some cases. We are a fan of polyjacking even though we don’t provide that service (but we like it a lot and might provide it in the future).

At Anchor Foundation Repair, we know there are many options available to homeowners and want you to find the best one for you even if that means going elsewhere for your repairs. After 35+ years in business, we build trusting relationships by being open to and suggesting alternatives when they seem like a better choice for your home and situation.

Check out this article about mud jacking vs. polyjacking for concrete repair comparisons. We love a good *versus* article!