CHEMISTRY OF HYDRATION OF PORTLAND CEMENT

A REVIEW IS PRESENTED IN THREE PARTS: (1) STOICHIOMETRY. EVIDENCE OF THE FORMATION OF SPECIFIC HYDRATION PRODUCTS, INCLUDING HYDRATION PRODUCTS OF THE ALUMINATES AND ALUMINOFERRITES, IN PORTLAND CEMENT PASTES IS DISCUSSED. STATISTICAL ANALYSIS OF VARIATION OF THE EFFECT OF COMPOSITION OF CEMENT UPON THE NONEVAPORABLE WATER OF SATURATED PASTES LEADS TO CALCULATED WATER CONTENTS FOR MANY HYDRATION PRODUCTS THAT AGREE REASONABLY WELL WITH THE COMPOSITIONS OF THE PURE HYDRATES. (2) KINETICS. RATES OF HYDRATION OF THE INDIVIDUAL MAJOR COMPOUNDS IN CEMENT, DETERMINED BY QUANTITATIVE ANALYSES OF PASTES BY X-RAY DIFFRACTION, WERE CONSISTENT WITH EMPIRICAL RELATIONSHIPS BETWEEN HYDRATION OF CEMENT AND PROPERTIES OF HARDENED PASTES. METHODS FOR ESTIMATING THE MATURITY OF CONCRETE AFTER CURING FOR SPECIFIED TIME AND TEMPERATURE ARE DISCUSSED. (3) ENERGETICS. AS A FIRST APPROXIMATION, THE INTRINSIC HYDRATION CHARACTERISTICS OF CEMENTS CAN BE EXPRESSED IN TERMS OF THE COMPOSITIONS OF THE CEMENTS, BY LEAST SQUARES ANALYSES OF HEAT EVOLUTION AND CHEMICALLY COMBINED WATER. SECONDARY CHANGES OF THE HYDRATED CALCIUM ALUMINATE ARE INDICATED. SOME ASPECTS OF THE ROLES OF GYPSUM, ALKALIES, GLASS CONTENT, AND IGNITION LOSS OF THE ORIGINAL CEMENT ON HEAT EVOLUTION ARE CONSIDERED. THE EFFECT OF TEMPERATURES IN THE RANGE OF 4.4 TO 110 C ON THE RATE OF HYDRATION OF CEMENT CAN BE EXPRESSED BY THE ARRHENIUS EQUATION. /PCA/

• Authors:
  • Copeland, L E
• Publication Date: 0

Media Info

• Serial:
  • Portland Cement Assoc R & D Lab Bull
  • Issue Number: 0

Subject/Index Terms

• TRT Terms: Aluminates; Chemistry; Diffraction; Ferrites; Heat of hydration; Hydration; Kinetics; Least squares method; Moisture content; Pastes; Portland cement; Quantitative analysis; Statistical analysis; Stoichiometry; Temperature; X rays
• Uncontrolled Terms: X-ray diffraction
• Subject Areas: Data and Information Technology; Highways; Materials;

Filing Info

• Accession Number: 00213593
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 153
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM