soil conditions concrete settlement

Soil and Other Conditions Leading to Concrete Settlement, Part 1

When concrete surfaces develop cracks, gaps or other forms of damage that worsen over time, by far the most common cause of these issues is concrete settlement. Concrete that settles will often create significant issues like these and more, and will get worse and worse with each passing day they are not attended to.

At Lift-Up Concrete Lifting LLC, we’re proud to offer residential, commercial and even municipal concrete lifting and leveling services for any concrete settling or related concerns on your property. We also provide our clients with expertise on how to avoid future concrete settlement issues, which mostly involves understanding what causes concrete settlement in the first place so you can work to prevent it. This two-part blog will go over several conditions that may lead to concrete settlement, plus how they can be avoided.

Soil Conditioning or Makeup Issues

In many situations, the issues with concrete settlement will trace back to the soil that’s used in the area. Soil will often be treated before concrete slabs are installed, with either native soils (those already present in the area) or imported soils (those brought in by a concrete installer from elsewhere) potentially playing a role. If soil is not conditioned properly, including allowing for optimal moisture content, settlement issues often result.

Down related lines, the use of improper soils is a common cause of settlement. The use of “muck,” or “trash soil” in some concrete circles, will lead to less water resistance and support, making it far easier for concrete to sink and settle. The use of compacted clay and related soils, on the other hand, will provide excellent support and moisture prevention.

Compaction Concerns

One soil-related area that deserves its own section here is improper compaction. The soil underneath your concrete must be compacted to the proper level, usually to at least 95% of the maximum density allowed by the material – if not, it will not properly resist water, degradation and other risks.

Expansion Risks

On the flip side of compaction is the risk of expansion, which can also lead to cracks and gaps in concrete. Many clays that are used for concrete soil surfaces must be conditioned properly before being used – if not, they are prone to expanding and shrinking in massive ways, with swell potential up to 20% in many cases. This expansion heaves and cracks concrete – and when the moisture that caused it eventually leaves the material, it will shrink and sink back into the surface while retaining these harmful cracks.

For more on avoiding the risks of concrete settlement through proper soil attention and other areas, speak to the staff at Lift-Up Concrete Lifting LLC today.