ACI Concrete Flatwork Finishing Certification Practice Test

The critical factor in avoiding settlement cracking in concrete is maintaining a consistent temperature throughout the curing process. When concrete is cured at uneven temperatures, particularly if parts of the slab cool or warm at different rates, it can lead to differential shrinkage and tension stress within the material. This stress can cause cracking as the concrete settles or adjusts to its surrounding conditions. By ensuring that the temperature remains relatively stable, the concrete can cure uniformly, which significantly reduces the risk of cracks developing due to settlement.

Quick drying of the surface may lead to surface cracking, while using low-strength concrete mixes could compromise the overall integrity of the slab without directly addressing the issue of settlement cracking. Minimizing exposure to sunlight can help with surface temperature but does not ensure consistent temperature throughout the concrete mass, which is crucial for preventing cracks associated with uneven curing.