What is used to keep the surface of freshly poured concrete moist to prevent cracking?

• A. Sealing compound
• B. Plastic sheeting
• C. Water cure method
• D. Curing compound

Answer: (C)

The water cure method is effective for keeping the surface of freshly poured concrete moist, which is crucial in preventing cracking. This method involves continuously applying water to the concrete surface, ensuring that it remains hydrated during the curing process. When concrete is not kept moist, it dries too quickly, leading to shrinkage cracks as the water evaporates. The water cure method helps the concrete maintain adequate moisture levels, allowing for proper hydration and chemical reactions that contribute to strength development.

While other methods, like sealing compounds and curing compounds, are also used to retain moisture, they serve different purposes. Sealing compounds can be applied after the concrete has set to create a barrier against moisture loss. Plastic sheeting can be used to cover the concrete to minimize evaporation, but it does not provide the continuous moisture that the water cure method does. Therefore, the water cure method is specifically designed to keep the concrete moist during the critical initial curing period, making it the best answer to the question.