Expandability of Solid-Volume-Reducing Reactions of Alkali-Magnesite and Alkali-Dolomite

    Volume 19, Issue 1 (June 1997)

    ISSN: 0149-6123

    CODEN: CCAOAD

    Page Count: 7


    Tong, L
    Post doctoral fellow, Tsinghua University,

    Tang, M
    Professor of materials science, Nanjing University of Chemical Technology, Nanjing,

    Abstract

    The work presented in this paper concerns two solid-volume-reducing reactions between alkali-dolomite (ADR) and alkalimagnesite (AMR). It was found that the two reactions can cause considerable expansion of compacts made from dolomite or magnesite powder and 20% Portland cement when cured at 150 and 60°C in 10% KOH solution. The results confirmed an earlier suggestion that the formation and growth of crystalline products in a confined space may be expandable.

    The expandability of the alkali-magnesite reaction was first recognized by the authors using newly developed test methods—150°C autoclaving of concrete microbars and miniature rock prism tests. Although magnesite itself is rarely used as a concrete aggregate, it is reasonable to investigate the reaction since concrete aggregates may contain a certain amount of magnesite.


    Paper ID: CCA10019J

    DOI: 10.1520/CCA10019J

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    Author
    Title Expandability of Solid-Volume-Reducing Reactions of Alkali-Magnesite and Alkali-Dolomite
    Symposium , 0000-00-00
    Committee C01