Which of the following is essential for proper concrete curing?

Moisture retention is essential for proper concrete curing because it helps to maintain the necessary hydration of the cement particles, which is crucial for the development of strength and durability in concrete. When concrete is poured, it undergoes a chemical reaction known as hydration, where water reacts with the cement. If the concrete dries out before this process is complete, it can lead to incomplete hydration, resulting in reduced strength and an increased risk of cracking or surface scaling.

Maintaining moisture can be achieved through methods such as covering the surface with wet burlap, polyethylene sheeting, or using curing compounds that form a moisture-retaining film on the concrete surface. The goal is to keep the concrete damp for an adequate period, typically at least seven days, depending on the mix and environmental conditions, to ensure optimal strength development.

While other factors, such as temperature and additives, can influence curing, moisture retention remains the fundamental requirement for effective curing practices in concrete work.