How Do Mudjacking Contractors Detect Voids Under Concrete?

Mudjacking contractors lift and stabilize sunken concrete by using a cement slurry to fill voids in the underlying soil. Once the gaps are filled, pressure elevates and returns the concrete to a fixed, level position.

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Voids under concrete aren’t visible, which is why homeowners and businesses usually don’t realize they have a problem until a slab sinks or develops cracks.

So, how do professional mudjacking contractors know where to pump the cement mixture? Ground penetrating radar (GPR) is the key. Here’s how the technology works.

Void Detection with Ground Penetrating Radar

To detect voids under concrete, mudjacking contractors use a high-frequency, ground penetrating radar system.

The GPR equipment sends a radio pulse down into the ground. When the transmission reaches an anomaly in the soil, a reflected signal is sent to the receiver. The process is quick, accurate and inexpensive, and allows the contractor to effectively complete the repair process.

Interpreting the Ground Penetrating Radar Data

Not every reflected radio signal indicates a soil void. GPR also detects other subsurface structures, including underground utilities, pipes, tension cables, storage tanks and boulders.

So, how do mudjacking contractors tell the difference?

When GPR signals travel through different types of matter, the time it takes for the radio pulse to be reflected back to the receiver varies. Concrete, metal, PVC, wood, rock, soil voids and other subsurface materials can be identified through their unique dielectric and conductive properties.

These properties are displayed on the GPR unit’s LCD screen. Understanding the results can be a challenge because the data is presented as a wavy line map, not as actual images of the underground soil voids and objects. However, professional mudjacking contractors are highly-trained and can easily interpret the GPR data.

Do Voids Under Concrete Return After Mudjacking?

The specialized mudjacking mixture used to fill soil voids is incredibly strong and stable enough to keep the restored concrete slab in place for many years. In most cases, concrete lifting repairs last for about a decade, which is a great value, given how mudjacking is the cheapest method for fixing sunken concrete.

Mudjacking is definitely not a short-term fix. However, this approach to repair doesn’t eliminate the possibility that voids under concrete will return. If your property has poor soil conditions – such as inadequate compaction, erosion or expansive clay soil – voids may redevelop over time. In addition, if problems like tree root growth, burrowing animals and underground plumbing leaks aren’t addressed, future void development is more likely.

Do you have sunken concrete? If your home or business is in the greater Salt Lake City area, the professional mudjacking contactors at Lift Right Concrete can provide you with an expert repair at an affordable price.

Let Lift Right Concrete, the leading Northern Utah residential and commercial concrete lifting company, restore the integrity and stability of your sunken concrete. Contact our Grantsville or West Jordan today to schedule a consultation with Salt Lake City’s preferred mudjacking contractors.