Certified Facility Manager (CFM) Practice Exam

When hairline cracks form a map-like pattern on a concrete slab's surface, this condition is called?

1. Crazing

2. Cracking

3. Settling

4. Spalling

The correct answer is: Crazing

Crazing occurs when hairline cracks develop on the surface of a concrete slab, forming a network or map-like pattern. This phenomenon typically results from the drying process of the concrete, where rapid evaporation of moisture causes shrinkage, leading to these fine cracks. Crazing is usually cosmetic and does not necessarily signify structural issues, though it can be an indicator of poor curing or other environmental factors affecting the concrete. In contrast, general cracking encompasses a broader category that includes various types and sizes of cracks, not just those that form a pattern. Settling refers to the downward movement of the entire slab, often due to soil compaction or erosion, which can lead to uneven surfaces but doesn’t specifically describe the patterned cracks. Spalling is the flaking or chipping of the concrete surface, which can occur due to freeze-thaw cycles or other damaging processes, but again, it's not representative of the map-like crack pattern associated with crazing.