Cracks in concrete are a common occurrence and develop when the stresses in the material exceed its strength. This is usually due to the normal shrinkage of concrete as it hardens and dries. As a decorative concrete contractor, it is important to remember that these cracks are a natural part of the curing process and not caused by any fault of yours. Although there are repair options available to prevent the cracks from getting worse, there is no good way to make them disappear completely.
It is best to prepare your customers ahead of time so that they are aware of this fact. Narrow cracks are a common sight in concrete slabs and usually do not indicate any structural problems. In most cases, these are shrinkage cracks that form when the concrete cures. While there are many reasons for concrete slabs to crack, most of them do not lead to serious foundation or structural issues.
However, there are times when cracks can be a warning sign of underlying problems and it is important to check other aspects of the home to determine the severity. It is important to understand that cracks in concrete are very common and do not necessarily mean something is wrong. If the crack is stable and does not leak water, it does not indicate a structural problem. In such cases, the best thing a contractor can do is try to control cracking by properly preparing the subbase, making sure that the concrete is not too wet, using reinforcement where necessary, and correctly placing and spacing the crack control joints and expansion joints.
Sometimes, despite all precautions taken, cracks still occur naturally as the concrete cures and heats up, expanding in the process. In summer, it is possible for the slab to crack even before you can walk on it. One of the most common mistakes people make when looking at their garage floor is confusing a cold joint with concrete that has actually cracked. If the concrete does not meet industry standards or building code, then it may be necessary to demolish the slab and start over with an extreme solution. It is better than building on a weak foundation.
When you see a crack in the concrete slab or wall, it does not always mean something has been done wrong. Some types of cracks are inevitable and can be caused by crust-forming during the concrete stamping process due to improper trowel and placement of concrete. The thin top layer of concrete dries faster than the rest of the concrete, leading to these fine cracks. When there are other problems such as those above with a house, cracks in the garage floor become more worrying as they can be related to foundation problems. If you notice uneven cracks larger than 1 inch, it is often a sign of a larger problem that requires you to replace or repair the sidewalk or driveway. By using proper procedures and exercising care, you will get the best performance from your Holcim concrete. The addition of water to ready-mixed concrete increases the likelihood of segregation and excessive bleeding which will make the surface porous, weak and prone to cracking. While water is an essential ingredient in every concrete mix, too much water can lead to shrinkage cracks which often occur in the same pattern that should have been articulated (see figure).
These usually occur shortly after pouring and are due to shrinkage of concrete. When you hear someone talk about 4,000 psi concrete, they mean that it would take 4,000 pounds per square inch of pressure to crush it.