Which problem is associated with settling or heaving of concrete?

The problem associated with settling or heaving of concrete is improper leveling of floors. When concrete settles or heaves, usually due to changes in soil moisture levels, compaction issues, or frost heave, it can lead to uneven surfaces. This results in floors that are out of level, which can manifest as visible slopes, cracks, or even making doors and windows stick.

In contrast, the other options refer to positive characteristics or implications that do not align with the consequences of settling or heaving in concrete. Increased insulation and enhanced thermal efficiency suggest improvements in a structure's ability to retain temperature, while the formation of decorative patterns typically refers to aesthetic choices or effects rather than structural problems. Therefore, improper leveling of floors is the correct association with the issue of concrete settling or heaving.