What is an effective way of controlling the temperature of plastic concrete?

Controlling the temperature of plastic concrete is essential for achieving proper curing and strength development. Pouring early in the morning takes advantage of cooler temperatures, which can help reduce the temperature of the concrete mix upon placement. Additionally, substituting ice for water is an effective strategy because as the ice melts, it helps to lower the temperature of the mix. This is particularly important in warm weather conditions, where elevated temperatures can lead to rapid evaporation of moisture and potentially detrimental effects on the curing process.

Using ice in combination with early morning pouring not only reduces the initial pour temperature but also allows for more controlled hydration, minimizing the risk of thermal cracking due to temperature differentials. This practice is widely accepted in the construction industry as a reliable method to manage the thermal properties of the concrete mix while ensuring structural integrity.

The other options may not be effective for controlling temperature in the way that ice and timing do. Pouring late in the day could expose the concrete to warmer temperatures, while substituting sand for stones may affect the overall strength and durability of the concrete without directly addressing temperature management. Using a color additive does not influence temperature control; its effect is mainly aesthetic and does not contribute to the thermal properties of the concrete.