What is a common mistake made during concrete finishing?

Finishing too soon before the bleed water has evaporated is a common mistake made during concrete finishing. This occurs when workers attempt to add a finishing touch to the surface of the concrete while there is still water present on top from the bleed process. If finishing is done too early, the surface can become damaged, leading to issues such as dusting, spalling, or delamination.

Bleed water is an important factor to consider because it indicates that the concrete has not yet set sufficiently. Waiting for this water to evaporate ensures that the surface is solid enough to take finishing operations without compromising the integrity of the slab. Proper timing during the finishing process is crucial to achieving a durable and high-quality surface.

In contrast, while using too much water in the mix can weaken the concrete, or failing to allow for proper curing time can affect the long-term strength, these issues are not specific to the timing of finishing itself. Similarly, applying sealant immediately after pouring does relate to surface treatment but does not address the critical phase of finishing concerning bleed water.