Canadian Council of Independent Laboratories (CCIL) Practice Exam

The stable temperature for mixing concrete is essential to ensure proper curing and strength development. A temperature of 23 C +/- 2 C is typically recommended as it provides an optimal balance for hydration reactions that occur when water is added to the cement. At this temperature range, the hydration process proceeds effectively, enabling the concrete to achieve its intended strength while minimizing the risk of issues such as cracking or incomplete curing.

Higher temperatures can accelerate the hydration process too quickly, potentially leading to a weaker bond and increased risk of shrinkage cracks. Conversely, lower temperatures can slow down hydration, which may delay curing times and impact the concrete’s strength. Thus, maintaining a temperature around 23 C allows for consistency in the mixing and curing process, contributing to the overall quality and longevity of the concrete.