Concrete Lifting
Concrete Leveling and Lifting
Concrete lifting or raising is also called slabjacking, this is a great alternative to repair concrete slabs. There are two main methods used for raising concrete, mudjacking or polyurethane foam concrete raising.
Both processes are very similar. First holes are drilled into the concrete slab, then mud or polyurethane foam is pumped under the slab, thereby raising the slab. To finish the holes and old cracks are patched with a concrete mix and its finished.
What causes concrete to settle?
There are many things that can cause concrete to settle, all of which do not always require concrete replacement to fix.
Poor or improper compaction of the base before concrete was poured: The weight of the slab will further compact the base after curing, and settlement can happen quickly.
Climate: The Polar Vortex experienced last year by many in the northern hemisphere wreaks havoc on concrete slabs. Freezing and thawing causes slabs to expand when frost is in the ground. Frost causes concrete to heave or raise. When the ground thaws, the concrete will settle again, but many times not to where it was originally. This results in trip spots between shifting slabs.On the opposite end of the climate spectrum, heat and drought can cause expansive clay soils to shrink, causing concrete slabs to settle. When those clay soils receive much needed rain and expand, the concrete slabs become unlevel.
Erosion: Damaged water or sewer lines, improperly placed downspouts, excessive rain can all lead to washout of base materials under concrete causing slabs to settle.
Machine/Traffic Vibrations: Concrete slabs may move or settle in industrial or highway settings where there is frequent movement and heavy loads being transported. The vibrations from machinery and passing traffic can lead to the base compacting and slabs settling or moving. Case study
Slab Curl/Rocking Slabs: Slab curl occurs when a relatively large section of concrete is poured. During the curing process, the top slab may cure slightly faster causing the slab to curl, rock, and become unstable. Vibration can also cause slabs to settle.