ASTM C1679-14
Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry

Standard No.

ASTM C1679-14

Release Date

2014

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM C1679-17

Latest

ASTM C1679-22

Scope

5.1 Thermal power curves are used to evaluate the isothermal hydration kinetics of the combined mixture of different materials during the early period after being mixed with water. These isothermal power curves, or hydration profiles, may provide indications relative to setting characteristics, compatibility of different materials, sulfate balance and early strength development. The isothermal hydration profiles can also be used to evaluate the effects of compositions, proportions, and time of addition of materials as well as curing temperature. Special care must be used in evaluating extended retardation with paste specimens, which have been shown to overestimate the retardation of some mixtures containing cement, SCM, and admixtures.

5.2 This procedure can be used to measure the effect of chemical admixtures on the cement hydration profile. In many cases, the addition of chemical admixture changes the kinetics of cement hydration.

5.3 Although this technique has been used historically to understand issues related to setting and slump loss, it must be emphasized that isothermal calorimetry results cannot predict concrete performance definitely, either positively or negatively. Extensive verification in concrete at planned dosages and temperatures, and at higher dosages, is needed. Isothermal calorimetry is an effective tool to identify sensitivities, so that concrete testing can be efficiently planned and performed.

5.4 This practice provides a means of assessing the relative hydration performance of various test mixtures compared with control mixtures that are prepared in a similar manner.

5.5 The procedure and apparatus can be used to monitor the thermal power from pastes and mortars alone or in combination with chemical admixtures.

5.6 The isothermal calorimeter described here can be used to measure the thermal power and heat of hydration of mortars prepared independently or obtained by wet sieving from concrete in accordance with Practice C172.

1.1 This practice describes the apparatus and procedure for measuring relative differences in hydration kinetics of hydraulic cementitious mixtures, either in paste or mortar (see Note 1), including those containing admixtures, various supplementary cementitious materials (SCM), and other fine materials by measuring the thermal power using an isothermal calorimeter.

Note 1: Paste specimens are often preferred for mechanistic research when details of individual reaction peaks are important or for particular calorimetry configurations. Mortar specimens may give results that have better correlation with concrete setting and early strength development and are often preferred to evaluate different mixture proportions for concrete. Both paste and mortar studies have been found to be effective in evaluating concrete field problems due to incompatibility of materials used in concrete mixtures.

1.2 The values stated in SI units are to be regarded as stan......

ASTM C1679-14 Referenced Document

• ASTM C1005 Standard Specification for Reference Masses and Devices for Determining Mass and Volume for Use in Physical Testing of Hydraulic Cements
• ASTM C125 Standard Terminology Relating to Concrete and Concrete Aggregates
• ASTM C1602/C1602M Standard Specification for Mixing Water Used in the Production of Hydraulic Cement Concrete
• ASTM C172 Standard Practice for Sampling Freshly Mixed Concrete
• ASTM C219 Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• ASTM C305 Standard Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars of Plastic Consistency
• ASTM C403/C403M Standard Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance
• ASTM C511 Standard Specification for Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes
• ASTM C778 Standard Specification for Standard Sand

ASTM C1679-14 history

• 2022 ASTM C1679-22 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry
• 2017 ASTM C1679-17 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry
• 2014 ASTM C1679-14 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry
• 2013 ASTM C1679-13 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry
• 2009 ASTM C1679-09 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry
• 2008 ASTM C1679-08 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry
• 2007 ASTM C1679-07 Standard Practice for Measuring Hydration Kinetics of Hydraulic Cementitious Mixtures Using Isothermal Calorimetry