Sinking Slab Repair Using Mudjacking
Mudjacking attempts to lift a sunken concrete slab by pumping grout through a hole in the concrete, effectively pushing it up from below. This process has been used since the early 1900s. The process uses a mixture of locally available soils (sometimes including crushed limestone and/or cement for strength), producing a mud-like substance and thus the term "mudjacking."
It is a cheaper alternative to having replacement concrete poured. It is also usually less expensive than pressure grouting - however many companies have stopped doing this process in favor of pressure grouting.
Why concrete sinks...
There can be many reasons as to why concrete sinks: improper compaction of soils during or after the building process, water intrusion from bad drainage, and natural settlement.
Soils consist of solid particles and the spaces (voids) between these particles. However, void spaces in soil can cause big problems for buildings and concrete slabs. Concentrated loads, such as buildings or slabs, can literally squeeze air and water from soils. When this happens, the soil sinks and the buildings or slabs follow closely behind.
Steps To Lifting Concrete Slabs
Step 1) Injection holes are strategically drilled around the locations where the concrete is sunken and requires lifting.
Step 2) Once everything is prepped and the hose and materials are in place, the polyurethane foam is injected through the holes which fills the space underneath the concrete slab, using the concrete slab itself to drive the polyurethane foam into the crevices, thereby raising the concrete back to its original, correct level.
Step 3) Upon completion of leveling the concrete, the injection hole(s) are loaded discretely with new cement, allowing you to make use of your surface right away.
The downside of this process is poor quality concrete may crack and/or deteriorate when being lifted. This is especially true for slabs that are less than 4 inches in thickness. Cracks can also develop in the concrete during the lifting process.
Reasons To Lift or Raise Your Concrete:
- Safety. Trip hazards may harm you, your loved ones and allows your property to be open for unwanted liability.
- Cost. You can lift up your concrete for under half the cost of replacing the concrete slab.
- Time. Disruption is minimal. Raising concrete with poly foam often takes a couple of hours and is ready instantly upon completion.
- Appearance. Curb appeal of your home or business can be affected by uneven concrete and dropped surfaces.
- Structural Damage. If other parts of the structure rest on your concrete slab you may experience damage to those areas as well.
Benefits to concrete lifting or mudjacking:
- It can be done in virtually any weather. The material injected beneath the slab provides a strong base.
- There is little or no disruption to landscaping.
- Nothing needs to be moved off the slab, as the pump can lift the weight of the slab and anything you have placed on it.
- Driveways, patios, basement floors, warehouse floors, and concrete slabs of any kind can be repaired using the mudjacking method.