Concrete slabs are prone to cracking despite being one of the strongest and most durable surfaces. While some cracks may be preventable through proper coating and installation, others are inevitable and will occur over time. It is important for concrete slab owners to be aware of common types of cracks and be prepared to address them as they arise.
Plastic Shrinkage Concrete Cracks
These cracks occur when the concrete is still in its "plastic" state and has not fully hardened yet. When water begins to evaporate from the surface too quickly, it leaves behind voids or holes. These holes weaken the concrete surface and make it much more likely to crack.
These types of cracks can happen anywhere on your concretes surface
Wherever piping or other objects are inserted in the concrete you will find more cracks
The cracks can be 1 to 4 inches deep into the concrete
Avoid these cracks by not using an overly wet mixture because more water means more shrinkage
Control joints can help with lowering the chances of shrinkage
Expansion Concrete Cracks
Heat causes materials to expand, and concrete is no exception. When concrete expands due to high temperatures, it can push against anything in its path, causing stress on the concrete. When neither side can flex any further, the concrete will eventually crack.
Expansion joints are used to help reduce concrete’s ability to expand into other surfaces
Joints are the shock absorbers of concrete
With professionally installed concrete joints the chances of your concrete cracking reduce dramatically
Heaving Concrete Cracks
Another example of a common cause of concrete cracks is the freeze-thaw cycle, which occurs when the concrete goes through repeated cycles of freezing and thawing. When water freezes, it expands, and when it thaws, it contracts. This constant expansion and contraction can lead to cracks in the concrete over time.
Growing roots can have a similar effect on concrete as contraction and expansion. As roots grow, they push against the concrete and restrict its ability to move freely. When the concrete has no more room to grow, it can crack or lift. In some cases, the concrete may lift and settle back down without cracking, but eventually, cracking is likely to occur.
Settling Concrete Cracks
The ground underneath concrete is constantly shifting and settling due to living organisms, pipes, and roots, which can cause concrete slabs to crack over time.
The drying and sinking of soil can greatly affect the reaction of your concrete slab. In residential areas, if ductwork is installed for heating and ventilation under the slab, the change in pressure can cause the surface to crack. Additionally, if the soil becomes too dry or too moist, the chances of cracking increase.
Overloading the Slab
Concrete is undoubtedly strong, as proven by some of the longest-lasting buildings around the world. However, everything on the planet, including concrete, has its limits, and when those limits are exceeded, the possibility of extreme cracking arises.
Concrete mixes can have the strength of 5000+ PSI it means pounds per square inch
These types of cracks occur in both residential and commercial areas
Large recreational vehicles are advised to be kept off of concrete
Premature Drying Cracks
It's important not to rush the drying process of your concrete, as doing so can lead to the need for repairs and even replacement. Rapid drying can cause surface cracks that resemble spiderwebs, but these cracks are typically only cosmetic and do not affect the structural integrity of the concrete.
Be sure to know the weather before installing new concrete
Avoid impatience while waiting for concrete to dry
Hire a professional to pour and dry your concrete