Concrete is referred to as "green concrete" for how many days?

Concrete is referred to as "green concrete" typically for a period of 28 days after it has been poured. This designation comes from the fact that during this time, concrete continues to cure and gain strength. The hydration process in concrete doesn't cease immediately after pouring; rather, it gradually continues as moisture from the environment interacts with the cement particles.

The significant time frame of 28 days is rooted in standard construction practices, allowing for accurate assessments of the concrete’s compressive strength. Engineers and builders often use this period to determine when the concrete has reached sufficient strength for structural use or further construction activities. While the initial setting occurs much earlier, the 28 days is a conventional benchmark that also aligns with industry standards such as those from organizations like the American Concrete Institute.