STP935: Cleaning Efflorescences from Masonry

    Gauri, KL
    Professor and Chairman, University of Louisville, Louisville, KY

    Holdren, GC
    Associate professor, University of Louisville, Louisville, KY

    Vaughan, WC
    Industrial surveillance coordinator, Metropolitan Sewer District, Louisville, KY

    Pages: 11    Published: Jan 1986


    Abstract

    Salt efflorescences attack masonry in all parts of the world, but in the arid regions they are the major cause of masonry decay. The efflorescences crystallize repeatedly from saturated solutions and become hydrated, generating, in the confined pore space and under surface crusts, pressures large enough to overcome the strength of the masonry material.

    Common methods for removing these salts are washing with water and application of surface-active poultices. These methods have their shortcomings: the first tends to transport salts into deeper regions by capillary action while removing some salts from the surface; the second method, besides being highly cumbersome, may result in masonry damage due to the salt crystallizing at the poultice-masonry interface.

    This paper describes two suction techniques, one of which appears to eliminate these shortcomings while promising maximum removal of salt from large surfaces in the shortest possible time.

    Keywords:

    architectural preservation, masonry cleaning, efflorescences, historic preservation, masonry, masonry decay, masonry preservation, monuments, Sphinx, stone durability, weathering


    Paper ID: STP20012S

    Committee/Subcommittee: E06.24

    DOI: 10.1520/STP20012S


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