Concrete CrackingOctober 19, 2013
One guarantee with concrete is it’s going to crack. Cracking can be the result of one or a combination of factors such as applied loads, drying shrinkage, subgrade settlement, and thermal contraction. Cracking can’t be prevented but it can be significantly reduced or controlled when the causes are taken into account and preventative steps are taken.
Structural cracks on foundations most likely occur from settlement or horizontal loading such as hydrostatic pressure or heavy equipment next to the foundation. Diagonal cracks that extend nearly the full height of the wall are often an indication of settlement. Cracks that occur after hardening usually are the result of drying shrinkage, thermal contraction, or subgrade settlement. The major factors influencing the drying shrinkage properties of concrete are the total water content of the concrete. As the water content increases, the amount of shrinkage increases proportionally. In addition to the mix design, when and how the concrete is placed and treated post pour can greatly influence whether cracking occurs.
To the contractor, a main issue with concrete cracking is the public’s perception. As cracks can be unattractive many believe that if a crack appears, the concrete has failed. As stated before, cracks are going to occur, it’s whether the crack is a structural concern or if it’s leaking water. It’s important if a crack appears, an experienced professional reviews it so it can be properly diagnosed and determined if there should be a concern with the integrity of the product.
There are several other causes of concrete cracking as well as many procedures the concrete contractor can perform to avoid unnecessary cracking. For more information feel free to call or leave an email.