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SCIENCE

The Claim

In cement paste, cement and water chemically react in a process called hydration to form the binding material that holds the mixture together.

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The Short Version

The claim matches standard cement science. In cement paste, water reacts chemically with cement in hydration, producing solid hydrates—most importantly C-S-H—that bind the paste and give it strength. The statement is simplified, but the omitted details about different cement phases and secondary reactions do not change its core accuracy.

Caveats

  • The statement is a simplified description: cement contains multiple reactive phases, not a single chemical species.
  • The main binding phase is calcium-silicate-hydrate (C-S-H), while other hydration products such as portlandite and ettringite also form.
  • In blended cements or concrete with supplementary cementitious materials, additional later-age reactions can also contribute to binding and densification.

The Receipts

  1. Calcium silicate hydrate in cementitious systems: structure and role in strength development

    PubMed Central

  2. Hydration Processes of Four-Component Binders Containing a Low Amount of Portland Cement and Very High Amounts of Supplementary Cementitious Materials

    Materials (MDPI) via PubMed Central

  3. Concrete: Scientific Principles

    University of Illinois at Urbana-Champaign

  4. Hydration of Portland Cement

    Pennsylvania State University

  5. Hydration of portland cement: The effect of curing conditions

    National Institute of Standards and Technology (NIST)

  6. Reaction Mechanism of Organic Admixtures with Hydrating Cement Compounds

    Transportation Research Board (TRB)

  7. 水泥（Cement）（一） | 科學Online - 臺灣大學

    科學Online - 臺灣大學

  8. How Cement Is Made

    Portland Cement Association

  9. What is cement hydration?

    Maturix

  10. CIVL 1101 - Part 4 - Hydration of Portland Cement

    University of Memphis

+ 8 more sources — see the full list on Lenz

Filed Under

Cement Hydration