Sidewalks and driveways alike can be a common place for trips and falls as a result of uneven or broken concrete. Concrete is heavy, and when the soil foundations underneath the cement naturally settle incorrectly, concrete will sink. Concrete raising and mudjacking services are designed to repair that sunken concrete, without the cost or effort of replacing it. We’ve identified the main causes of outdoor concrete that sinks to help you understand this issue.

So, Why Does Concrete Sink?

Soil Shrinkage, Compaction, and Settling

Underneath the concrete laid on the ground is various types and levels of soils. Each type of soil has different load-bearing capacities, which leads to compaction and settling after unspecified periods of time. Soil that contains large amounts of clay or silt will shrink when it gets dry, creating more room beneath the concrete slab, and make it susceptible to sinking. Unsupported slabs will sink because of soil beneath the concrete slabs that settles and compacts, making the slab susceptible to cracking and uneven surfaces.

Washout of Soil

As general rainfall and water activity takes place, water moves underneath the concrete slabs. It can wash away the soil that supports the weight of the concrete, creating a void or space in the foundation beneath the slab. Space can lead to sinking, breaking or caving of the concrete slab.

Insufficient Foundation

Sometimes concrete is poured over a flat soil foundation, and other times it is not. Whether the foundation beneath the concrete was quality to begin with or not, over time the soil moves, shrinks, and settles, creating voids that allow sinking and breakage.

Concrete sinks for a variety of reasons, but the common problem is always soil. Whether it’s good soils, bad soil, dry soil, or moved soil, the foundation that concrete sits on is what will determine how it shifts or falls over time.

Concrete raising and mudjacking are common solutions in fixing an insufficient soil foundation. By pumping grout and soil mixtures into small holes in the concrete, insufficient foundations are a quick fix for contractors who perform slabjacking like AAA Concrete Raising.