Heat of Hydration

Definition

Heat of Hydration is the thermal energy given off by concrete, masonry, or gypsum as it cures.

Purpose

The heat of hydration is an important aspect of the curing process for materials like concrete and gypsum. It influences the strength development and durability of these materials. Managing the heat of hydration is crucial in preventing thermal cracking and ensuring the integrity of large concrete structures.

Examples of Use

1. Concrete Curing: Monitoring heat generation in large pours to prevent cracking.
2. Gypsum Plastering: Understanding heat release during the setting process to manage application and drying times.
3. Masonry Construction: Ensuring proper curing conditions for brick and stone structures.
4. Cement Production: Analyzing heat of hydration for different cement compositions to optimize performance.

Related Terms

• Curing: The process of maintaining adequate moisture, temperature, and time to allow concrete to achieve desired properties.
• Hydration: The chemical reaction between cement and water that produces hardened concrete.
• Exothermic Reaction: A chemical reaction that releases heat.
• Thermal Cracking: Cracks that develop in concrete due to excessive temperature gradients.

Notes

Controlling the heat of hydration is especially important in massive concrete structures, where excessive heat can lead to internal stresses and cracking. Techniques such as cooling pipes, using low-heat cement, and phased construction are employed to manage this heat.