ISO 29582-1:2009

Overview

ISO 29582-1:2009 - Methods of testing cement: Determination of the heat of hydration - Part 1: Solution method describes a standardized laboratory procedure to measure the heat of hydration of cements and hydraulic binders using solution calorimetry (the solution method). Results are expressed in joules per gram (J/g) of cement. The procedure is applicable to cements and hydraulic binders irrespective of chemical composition and supports quality control, research and material specification.

Key topics and technical requirements

• Principle: Measure the heat released by dissolving anhydrous cement and standardized hydrated cement samples in a defined acid mixture; the heat of hydration equals the difference between their heats of solution.
• Standardized hydration conditions: examples given include a water/cement ratio of 0.40, neat paste storage at 20.0 ± 0.2 °C, and specified curing periods (commonly 7 days for best correlation with other methods).
• Acid mixture: analytical-grade mixture formulation is specified (e.g., HF/HNO3 proportions), with safety warnings for hydrofluoric acid handling.
• Sample preparation: procedures for preparing anhydrous and hydrated cement samples, including mixing, vial storage and prevention of CO2/water uptake.
• Calorimeter and apparatus: description of a suitable calorimeter (insulated flask, thermometer, stirrer, funnel). Suggested calorimeter characteristics include a typical flask volume (~650 ml) and requirements for acid-resistant materials.
• Calorimeter calibration: determination of calibration characteristics such as corrected temperature increase, thermal leakage coefficient K (target K